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                                                                    EXHIBIT 10.1

                         CLASS A-1 CALL OPTION AGREEMENT

         CLASS A-1 CALL OPTION AGREEMENT, dated as of March 8, 2004 (this
"Agreement"), among CORPORATE ASSET BACKED CORPORATION, a Delaware corporation
(the "Depositor"), as the sole initial Option Holder (as defined below), UBS
SECURITIES LLC ("UBS Securities"), as the initial purchaser from the Depositor,
and initial and sole holder at the time of execution of this Agreement, of the
Class A-1 Certificates (as defined below), and U.S. BANK TRUST NATIONAL
ASSOCIATION, a national banking association, as the agent appointed by UBS
Securities to act on behalf of UBS Securities and its successors under this
Agreement and the Trust Agreement (as defined below), with respect to the
options granted by UBS Securities to the Depositor under this Agreement. U.S.
Bank Trust National Association, acting for UBS Securities and any subsequent
transferee of a Class A-1 Certificate as agent with respect to such options as
set forth in more detail below, is referred to herein as the "Option Agent."

                                   WITNESSETH:

         WHEREAS, the Depositor has established the CABCO Series 2004-1 Trust
(Goldman Sachs Capital I) (the "Trust") as a common law trust under the laws of
the State of New York pursuant to the Trust Agreement, dated as of March 8, 2004
(the "Trust Agreement"), between the Depositor and U.S. Bank Trust National
Association, as Trustee and Option Agent; and

         WHEREAS, the Trust issued certificates to the Depositor in two classes
evidencing in the aggregate the beneficial interests in all the assets of the
Trust; and

         WHEREAS, the Depositor is selling all the Class A-1 Callable
Certificates issued by the Trust (the "Class A-1 Certificates") to UBS
Securities, as underwriter pursuant to the Underwriting Agreement, dated March
1, 2004 (the "Underwriting Agreement"), between the Depositor and the
Underwriter, for resale to investors, and is selling all the Class B-1 Callable
Certificates issued by the Trust (the "Class B-1 Certificates") to UBS
Securities, as initial purchaser under the Purchase Agreement, dated March 1,
2004, between the Depositor and UBS Securities; and

         WHEREAS, as partial consideration for its purchase of each Class A-1
Certificate, UBS Securities intends to grant to the Depositor an option to
repurchase that Class A-1 Certificate upon the terms and subject to the
conditions set forth in this Agreement; and

         WHEREAS, each option relating to a single Class A-1 Certificate is
referred to herein as a "Class A-1 Option," or the "related Class A-1 Option,"
as the context shall require; and

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         WHEREAS, ownership of the Class A-1 Options granted hereunder shall be
evidenced by one or more option certificates issued hereunder in definitive
physical form, each of which option certificates shall be substantially in the
form attached as Exhibit C, and each of which option certificates in definitive
physical form shall evidence the number of Class A-1 Options set forth on its
face; and

         WHEREAS, the Trust Agreement provides that each subsequent purchaser of
a Class A-1 Certificate agrees, by such purchase, to assume the obligation to
perform the related Class A-1 Option, and further agrees to appoint U.S. Bank
Trust National Association as its agent to act on its behalf with respect
thereto under this Agreement and the Trust Agreement; and

         WHEREAS, upon each such transfer of a Class A-1 Certificate (and the
automatic assumption of the obligations under the related Class A-1 Option by
the transferee), the transferor of the Class A-1 Certificate shall be released
from its obligation to perform the related Class A-1 Option, and the
transferor's appointment of U.S. Bank Trust National Association as its agent
with respect thereto shall terminate; and

         WHEREAS, as partial consideration for its purchase of each Class B-1
Certificate, UBS Securities intends to grant to the Depositor an option (each, a
"Class B-1 Option") to repurchase that Class B-1 Certificate upon the terms and
subject to the conditions set forth in the Class B-1 Call Option Agreement,
dated as of March 8, 2004 (the "Class B-1 Option Agreement"), among the
Depositor, as the sole initial holder of the Class B-1 Options, UBS Securities,
as the initial purchaser from the Depositor, and initial and sole holder at the
time of execution of such agreement, of the Class B-1 Certificates, and U.S.
Bank Trust National Association, acting as option agent for the holders of the
Class B-1 Certificates from time to time, which Class B-1 Options shall be
granted on terms (other than Call Price) substantially similar to those
contained in this Agreement;

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

                                   ARTICLE I

                                  Definitions

         Section 1.1. Definitions.

         As used in this Agreement, unless the context otherwise requires, the
following terms have the following respective meanings:

                  "Affiliate" has the meaning specified in the Trust Agreement.

                  "Agreement" has the meaning specified in the preamble to this
         Agreement.

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                  "Business Day" has the meaning specified in the Trust
         Agreement.

                  "Call Date" means, with respect to any Class A-1 Option, the
         date on which settlement of that Class A-1 Option occurs pursuant to
         Section 2.2(d).

                  "Call Notice" has the meaning specified in Section 2.2(b).

                  "Call Options" means, collectively, the Class A-1 Options and
         the Class B-1 Options.

                  "Call Price" means, with respect to each Class A-1 Option, an
         amount equal to the sum of (i) the outstanding certificate principal
         balance on the Call Date of the Class A-1 Certificate subject to such
         Class A-1 Option, plus (ii) any accrued and unpaid interest on such
         Class A-1 Certificate through the Call Date, plus (iii) if the Call
         Date occurs prior to March 8, 2009, as a result of the delivery of a
         notice of a tender offer for, a redemption or repurchase of or an
         unscheduled payment on some or all of the Underlying Securities, an
         amount equal to $1.50 per Class A-1 Certificate.

                  "Certificate Notional Amount" has the meaning specified in the
         Trust Agreement.

                  "Certificate Principal Balance" has the meaning specified in
         the Trust Agreement.

                  "Certificate Register" has the meaning specified in the Trust
         Agreement.

                  "Certificateholder" means each Person in whose name a
         Certificate is registered on the Certificate Register.

                  "Certificates" means the Class A-1 Certificates and the Class
         B-1 Certificates.

                  "Class A-1 Call Option Certificate" has the meaning specified
         in Section 2.1.

                  "Class A-1 Certificates" has the meaning specified in the
         recitals to this Agreement.

                  "Class A-1 Option" has the meaning specified in the recitals
         to this Agreement.

                  "Class B-1 Certificates" has the meaning specified in the
         recitals to this Agreement.

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<PAGE>

                  "Class B-1 Option" has the meaning specified in the recitals
         to this Agreement.

                  "Class B-1 Option Agreement" has the meaning specified in the
         recitals to this Agreement.

                  "Closing Date" has the meaning specified in the Trust
         Agreement.

                  "Depositor" has the meaning specified in the preamble to this
         Agreement.

                  "Depositor Order" has the meaning specified in the Trust
         Agreement.

                  "Exchange Act" means the Securities and Exchange Act of 1934,
as amended.

                  "Option Agent" means U.S. Bank Trust National Association, in
         its capacity as option agent appointed under this Agreement, or any
         successor in such capacity.

                  "Option Holder" means, initially, the Depositor, and
         thereafter with respect to each Class A-1 Option, the Person to whom
         such Class A-1 Option has been transferred as provided herein.

                  "Person" means any individual, corporation, estate, limited
         liability company, partnership, joint venture, association, joint stock
         company, trust (including any trust beneficiary), unincorporated
         organization or government or any agency or political subdivision
         thereof.

                  "Protected Purchaser" has the meaning specified in the Uniform
         Commercial Code as is in effect in the State of New York.

                  "Rating Agency" has the meaning specified in the Trust
         Agreement.

                  "Responsible Officer" has the meaning specified in the Trust
         Agreement.

                  "Securities Act" has the meaning specified in Section 2.4(a).

                  "SEC Reporting Failure" means that (i) The Goldman Sachs
         Group, Inc. has suspended its reporting under the Exchange Act at a
         time when the Exchange Act reporting requirements applicable to the
         Trust have not been suspended or terminated, and either (x) the
         suspension of Exchange Act reporting by the Underlying Securities
         Guarantor continues for a period of at least one year, or (y) the
         Underlying Securities Guarantor announces or takes measures that
         demonstrate in connection with such suspension or at any time
         thereafter, that it will no longer be a reporting company under the
         Exchange Act; (ii) the Class A-1 Certificates have been be removed from
         the DTC book-entry system; (iii)

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         definitive certificates representing the Class A-1 Certificates have
         been issued to the beneficial owners of the Class A-1 Certificates; and
         (iv) The Goldman Sachs Group, Inc. has not resumed filing Exchange Act
         reports within 60 days of such distribution.

                  "Transfer" means, with respect to any Class A-1 Option, the
         assignment by the Option Holder of all rights and delegation by the
         Option Holder of all obligations under such Class A-1 Option, and
         "Transferee" and "Transferor" shall have correlative meanings.

                  "Transfer Confirmation" has the meaning specified in Section
         2.4(c).

                  "Trust" has the meaning specified in the recitals to this
         Agreement.

                  "Trust Agreement" has the meaning specified in the recitals to
         this Agreement.

                  "Trustee" means the Trustee from time to time under the Trust
         Agreement.

                  "UBS Securities" has the meaning specified in the preamble to
         this Agreement.

                   "Underlying Securities" means the $62,500,000 principal
         amount of 6.345% Capital Securities issued by Goldman Sachs Capital I,
         and fully and unconditionally guaranteed by Goldman Sachs Group, Inc.,
         deposited in the Trust, exclusive of interest accrued from and
         including February 20, 2004, to but excluding the Closing Date (which
         interest has been retained by the Depositor), unless the context
         otherwise requires.

                  "Underlying Securities Default" means an Event of Default (as
         defined in the Underlying Securities Trust Agreement) under the
         Underlying Securities, or any event that, with the giving of notice or
         passage of time, or both, would be an Event of Default (as defined in
         the Underlying Securities Trust Agreement).

                  "Underlying Securities Trust Agreement" has the meaning
         specified in the Trust Agreement.

                  "Underwriting Agreement" has the meaning specified in the
         recitals to this Agreement.

         Section 1.2. Interpretive Provisions.

         For all purposes of this Agreement, except as otherwise expressly
provided or unless the context otherwise requires:

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<PAGE>

                  (a)      the terms defined in this Article have the meanings
         assigned to them in this Article and include the plural as well as the
         singular, and nouns and pronouns of each gender include each of the
         other genders;

                  (b)      all accounting terms not otherwise defined in this
         Agreement have the meanings assigned to them in accordance with
         generally accepted accounting principles in the United States;

                  (c)      whenever the words "include," "includes" or
         "including" are used in this Agreement, they shall be deemed to be
         followed by the words "without limitation";

                  (d)      any reference in this Agreement to any statute,
         regulation or agreement is a reference to such statute, regulation or
         agreement as supplemented or amended from time to time;

                  (e)      any reference in this Agreement to any Person is a
         reference to such Person and such Person's successors and assigns;

                  (f)      the Article and Section headings in this Agreement
         are for convenience only and shall not affect the construction of this
         Agreement;

                  (g)      when a reference is made in this Agreement to
         Articles, Sections, Exhibits or Schedules, such reference is to
         Articles or Sections of, or Exhibits or Schedules to, this Agreement;
         and

                  (h)      all references to a specific time are references to
         New York City time.

                                   ARTICLE II

                              THE CLASS A-1 OPTIONS

         Section 2.1 Grant of Class A-1 Options; Option Holders Are
Beneficiaries.

         (a)      UBS Securities, as the initial purchaser of the Class A-1
Certificates from the Depositor, and initial and sole Certificateholder of the
Class A-1 Certificates at the time of execution of this Agreement, hereby grants
the Class A-1 Options to the Depositor. To evidence such grant, the Option Agent
is hereby directed to concurrently issue to the Depositor an option certificate
in definitive registered physical form (a "Class A-1 Call Option Certificate")
in the Depositor's name in substantially the form attached as Exhibit C,
evidencing 2,500,000 Class A-1 Options, and to register the Depositor's
ownership of such Class A-1 Options in the register referred to in Section
2.4(e).

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<PAGE>

         (b)      Each Option Holder shall be an express beneficiary of this
Agreement, entitled to enforce this Agreement directly in its own name against
the Option Agent and the Certificateholders holding Class A-1 Certificates.

         Section 2.2. Manner of and Conditions to Exercise.

         (a)      Subject to the terms and conditions of this Agreement, each
Class A-1 Option may be exercised by the relevant Option Holder on any Business
Day occurring (i) on or after March 8, 2009, (ii) at any time following the
occurrence of an Underlying Securities Default or an SEC Reporting Failure, or
(iii) at any time in connection with a tender offer for, a redemption or
repurchase of or an unscheduled payment on the Underlying Securities. The
parties acknowledge that, under the Trust Agreement, if the Trustee receives any
announcement, proposal or notice of a redemption or repurchase of, tender offer
for or an unscheduled payment on any Underlying Securities, the Trustee will be
required to deliver a copy of that document to the Option Agent within two
Business Days. The Option Agent agrees to send a copy of each such document
received from the Trustee to each Option Holder on the same day it is received
from the Trustee.

         (b)      An Option Holder may exercise any Class A-1 Option only upon
satisfaction of each of the following conditions:

                  (i)      Simultaneously with such exercise, the Option Holder
         shall exercise Class B-1 Options with respect to a number of Class B-1
         Certificates equal to the number of Class A-1 Options being exercised.

                  (ii)     The aggregate Certificate Principal Balance of the
         Class A-1 Certificates subject to the Class A-1 Options exercised by
         such Option Holder on such Call Date shall be an integral multiple of
         $1,000.

                  (iii)    Not fewer than 15 days nor more than 60 days prior to
         the proposed Call Date, the Class A-1 Option Holder shall deliver a
         notice substantially in the form attached as Exhibit A (each, a "Call
         Notice") to each of the Option Agent and the Trustee specifying the
         number of Class A-1 Options being exercised, the proposed Call Date
         with respect to such Class A-1 Options, and the account to which the
         Trustee shall deliver the Underlying Securities deliverable pursuant to
         Section 2.15 of the Trust Agreement upon exchange of the Class A-1
         Certificates purchased as a result of such exercise; provided, however,
         that with respect to any exercise of a Class A-1 Option pursuant to
         Section 2.2(a)(ii) or 2.2(a)(iii), the Call Notice shall be delivered
         to the Option Agent and the Trustee not later than two Business Days
         prior to the proposed Call Date.

                  (iv)     (A) As a result of the exercise, the aggregate
         Certificate Principal Balance of the Class A-1 Certificates and the
         aggregate Certificate Notional Amount of Class B-1 Certificates,
         respectively, purchased by the Option Holder is in each case not less
         than $6,250,000 (or, if less, the aggregate outstanding

                                       7
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         Certificate Principal Balance of all the outstanding Class A-1
         Certificates or aggregate outstanding Certificate Notional Amount of
         all the outstanding Class B-1 Certificates, as applicable), and (B)
         after giving effect to such exercise and the related exchange of
         Certificates for Underlying Securities pursuant to Section 2.15 of the
         Trust Agreement, (I) unless the Option Holder has exercised all Call
         Options held by it, the remaining aggregate Certificate Principal
         Balance of Class A-1 Certificates and Certificate Notional Amount of
         Class B-1 Certificates subject to options held by such Option Holder
         that have not been exercised is in each case not less than $6,250,000,
         and (II) the remaining aggregate Certificate Principal Balance of Class
         A-1 Certificates and Certificate Notional Amount of Class B-1
         Certificates, if greater than zero, is in each case not less than
         $6,250,000.

                  (v)      (A) Unless the Option Holder has exercised the Class
         A-1 Options in connection with a tender offer, the Option Holder shall
         have made payment of the Call Price under all of the exercised Call
         Options to the Option Agent, by wire transfer in immediately available
         funds, no later than 10:00 a.m. on the proposed Call Date, and (B) if
         the Option Holder has exercised the Class A-1 Options in connection
         with a tender offer, the Trustee shall have received payment of the
         tender price from the Underlying Securities Issuer or other purchaser
         of the Underlying Securities relating to the Certificates subject to
         all of the exercised Call Options (or with respect to the portion of
         the Call Options deemed exercised as provided in Section 2.2(e), if
         less than all Underlying Securities tendered by the Trustee pursuant to
         Section 2.15 of the Trust Agreement have been purchased), in
         immediately available funds, no later than 10:00 a.m. on the later of
         (i) the Call Date specified in the Call Notice, or (ii) the earlier to
         occur of the date immediately following the date on which the tender
         offer is consummated or the date on which it expires unconsummated.

         If Call Options are held or exercised by two or more Affiliates, then
all Call Options held or exercised by such Affiliates on the same date will be
treated as being held or exercised by a single Option Holder for purposes of
satisfying the conditions listed in clauses (b)(i) through (b)(v) above.

         (c)      The Option Agent shall notify the Trustee immediately upon its
receipt of a Call Notice. If the number of Class A-1 Certificates specified in
such Call Notice is less than the outstanding number of Class a-1 Certificates,
the Trustee shall select the Class A-1 Certificates to be purchased by the
Option Holder. The Class A-1 Certificates so selected shall be a pro rata
portion of the Class A-1 Certificates held by each Certificateholder, provided
that purchases of a fraction of a single Class A-1 Certificate will not be made,
and the Trustee shall round up or down the number of Class A-1 Certificates to
be purchased from each Certificateholder to avoid such fractional purchases.

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<PAGE>

         (d)      On the date specified in the applicable Call Notice, upon
satisfaction of the conditions specified in Section 2.2(b), the Option Agent
shall (x) notify the Trustee of its receipt of the Call Price and the
satisfaction of such conditions and (y) instruct the Trustee to (i) register the
Class A-1 Certificates selected as provided in Section 2.2(c) in the name of the
Option Holder (or, in the case of called Class A-1 Certificates held in
book-entry form, cause such Class A-1 Certificates to be transferred to the
account of the Option Holder) and (ii) exchange the called Class A-1
Certificates, together with the Class B-1 Certificates called pursuant to the
Class B-1 Options on the same Call Date, for an aggregate principal amount of
Underlying Securities equal to the aggregate outstanding Certificate Principal
Balance of such Class A-1 Certificates as provided in Section 2.15 of the Trust
Agreement; and (z) (I) unless the Call Options were exercised in connection with
a tender offer, remit the amount of the Call Price received from the Option
Holders to the Trustee and instruct the Trustee to pay to each Certificateholder
from whom the Class A-1 Certificates were purchased the Call Price in respect of
such Class A-1 Certificates, or (II) if the Call Options were exercised in
connection with a tender offer, pay to the Option Holder the difference between
the tender offer proceeds and the Call Price. The parties acknowledge that the
Call Price for a call in connection with a tender offer shall be deducted from
the proceeds of a tender offer received by the Trustee, and paid to the holders
of the called Certificates pursuant to Section 2.15(j) of the Trust Agreement.

         (e)      Delivery of a Call Notice does not give rise to an obligation
on the part of the Option Holder to pay the Call Price. The Call Notice shall
automatically expire (i) if the Call Option is being exercised other than in
connection with a tender offer, and the Option Holder has not paid the Call
Price to the Option Agent by 10:00 a.m. on the Call Date, or (ii) in the case of
a tender offer, if the Trustee has not received payment of the tender offer
proceeds from the Underlying Securities Issuer or other purchaser by 10:00 a.m.
on the later of (A) the date specified for settlement in the Call Notice, or (B)
the earlier to occur of the date immediately following the date on which the
tender offer is consummated or the date on which it expired unconsummated.
Furthermore, if any Class A-1 Call Options are exercised in connection with a
tender offer and fewer than all the Underlying Securities are tendered by the
Trustee as provided in Section 2.15 of the Trust Agreement, or fewer than all
the Underlying Securities tendered by the Trustee pursuant to Section 2.15 of
the Trust Agreement are accepted for payment and paid for under the tender
offer, then the number of Class A-1 Call Options deemed exercised will be
reduced so that the Certificate Principal Balance of the Class A-1 Certificates
subject to such exercised Class A-1 Call Options is equal to the principal
amount of Underlying Securities tendered by the Trustee that are accepted for
payment and paid for, and the Class A-1 Call Options deemed not exercised will
remain outstanding. In addition, if the tender offer is terminated by the person
making the tender offer before any Underlying Securities are accepted for
payment and paid for, or if all tenders by the Trustee of Underlying Securities
are rejected, then the applicable Call Notice will be of no further force and
effect, and any related Class A-1 Call Options will be deemed not exercised and
will remain outstanding. If a Call Notice shall expire for any reason provided
for in

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this Section 2.2(e), none of the Option Holder, the Option Agent, the Trustee or
any Certificateholder shall have any obligation with respect to the Call Notice,
and the expiration of a Call Notice shall in no way affect the Option Holder's
right to deliver a Call Notice at a later date.

         Section 2.3. Legends on Certificates.

         Each Class A-1 Certificate shall bear a legend notifying any
Certificate Holder of the existence and terms of the Class A-1 Option to which
that Class A-1 Certificate is subject, in substantially the following form:

                  BY ACQUIRING OR ACCEPTING ANY INTEREST IN THIS CERTIFICATE,
         YOU ACKNOWLEDGE THAT THIS CERTIFICATE IS SUBJECT TO A PURCHASE OPTION
         GRANTED TO CORPORATE ASSET BACKED CORPORATION, A DELAWARE CORPORATION
         (THE "DEPOSITOR"), BY UBS SECURITIES LLC UNDER THE CLASS A-1 CALL
         OPTION AGREEMENT, DATED AS OF MARCH 8, 2004 (THE "CALL OPTION
         AGREEMENT"), AMONG THE DEPOSITOR, AS THE SOLE INITIAL OPTION HOLDER,
         UBS SECURITIES LLC, AS THE INITIAL PURCHASER FROM THE DEPOSITOR, AND
         SOLE HOLDER AT THE TIME OF SUCH GRANT, OF THE CLASS A-1 CERTIFICATES,
         AND U.S. BANK TRUST NATIONAL ASSOCIATION, A NATIONAL BANKING
         ASSOCIATION, ACTING AS OPTION AGENT FOR THE CLASS A-1
         CERTIFICATEHOLDERS WITH RESPECT TO THE CLASS A-1 OPTIONS (THE "OPTION
         AGENT"), WHICH OBLIGATIONS HAVE BEEN ASSUMED BY EACH SUBSEQUENT HOLDER
         OF SUCH CLASS A-1 CERTIFICATES; YOU AGREE TO ASSUME THE OBLIGATION OF
         YOUR TRANSFEROR TO PERFORM SUCH CLASS A-1 OPTION; AND YOU ACKNOWLEDGE
         THAT YOUR TRANSFEROR HAS BEEN RELEASED FROM ITS OBLIGATION TO PERFORM
         SUCH CLASS A-1 OPTION. THE CALL OPTION AGREEMENT PERMITS THE HOLDER OF
         THE RELATED CLASS A-1 OPTION TO PURCHASE THIS CERTIFICATE FROM YOU,
         WITHOUT YOUR CONSENT, AT THE TIMES AND ON THE CONDITIONS SPECIFIED IN
         THE CALL OPTION AGREEMENT AT THE CALL PRICE SPECIFIED IN THAT
         AGREEMENT. THE CLASS A-1 OPTION MAY BE TRANSFERRED FROM TIME TO TIME.
         UPON THE EXERCISE OF THE RELATED CLASS A-1 OPTION IN THE MANNER
         SPECIFIED IN THE CALL OPTION AGREEMENT, THE CLASS A-1 CERTIFICATE WILL
         BE TRANSFERRED TO THE RELEVANT CLASS A-1 OPTION HOLDER BY THE TRUSTEE,
         AND YOU WILL BE PAID THE CALL PRICE FOR THIS CERTIFICATE IN ACCORDANCE
         WITH THE TERMS OF THE CALL OPTION AGREEMENT, WITHOUT THE REQUIREMENT OF
         ANY FURTHER ACTION BY YOU, EXCEPT THAT IF THE CLASS A-1 CERTIFICATES
         ARE HELD IN DEFINITIVE FORM AT SUCH TIME YOU WILL NOT RECEIVE SUCH

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<PAGE>

         CALL PRICE UNLESS AND UNTIL YOU SURRENDER THIS CERTIFICATE.

         Section 2.4. Transfer of Class A-1 Options.

         (a)      Each of the parties to this Agreement acknowledges that the
Class A-1 Options are being issued in a transaction exempt from registration
under the U.S. Securities Act of 1933 (the "Securities Act") and that the Class
A-1 Options have not been and will not be registered under the Securities Act or
any applicable state securities law of any state and may not be offered, sold,
pledged or otherwise transferred except in a transaction registered pursuant to
the Securities Act or exempt from registration under the Securities Act, and
otherwise in accordance with the terms of this Agreement.

         (b)      Promptly following the sale of the Class A-1 Certificates to
UBS Securities pursuant to the Underwriting Agreement and the related grant of
the Class A-1 Options by UBS Securities to the Depositor as provided in Section
2.1, and in any event within 45 days thereafter, the Depositor shall Transfer
100% of the Class A-1 Options to one or more unaffiliated third parties through
UBS Securities, as agent pursuant to the Placement Agency Agreement, dated March
1, 2004, between the Depositor and UBS Securities. Subject to the terms and
conditions set forth in this Article II, each Option Holder may Transfer some or
all of the Class A-1 Options it holds to one or more other Persons at any time
and from time to time, provided that under no circumstances may any Class A-1
Option be re-Transferred to the Depositor.

         (c)      The Transfer of any Class A-1 Option shall be effected by the
delivery of the relevant Class A-1 Call Option Certificate to the Option Agent
for registration in the name of the Transferee as set forth in Section 2.4(e)
hereof, in each case with a form of assignment executed by the Transferor and
the execution and delivery by the Transferor, the Transferee and the Option
Agent of a confirmation substantially in the form attached as Exhibit B (a
"Transfer Confirmation").

         (d)      Each Class A-1 Option may be Transferred only in full. No
fractional interest in a Class A-1 Option may be transferred, and no interest in
a Class A-1 Option may be transferred except in connection with a Transfer of
all the rights and obligations of the Option Holder under and in respect of the
Class A-1 Option.

         (e)      The Option Agent shall keep a register in which it shall
provide for the registration of the Class A-1 Options and the registration of
transfers of the Class A-1 Options. The Option Agent shall record in such
register (w) the name and registered address of each Option Holder, (x) the
number of Class A-1 Options held by each Option Holder, (y) the Transfer of any
Class A-1 Options, and (z) the number of Class A-1 Options exercised by each
Option Holder and the number of Call Options cancelled as provided in Section
2.5. The Trustee and the Option Agent may treat the Person in whose name any
Class A-1 Option is registered on such register as the owner of that Class A-1

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Option for all purposes, and the Trustee and the Option Agent shall not be
affected by any notice to the contrary.

         Section 2.5. Pro Rata Reduction of Class A-1 Options Upon Partial
Redemption of Underlying Securities.

         If Underlying Securities are redeemed in part by the Underlying
Securities Issuer and the Option Holders do not exercise Call Options with
respect to all the Underlying Securities redeemed in such partial redemption,
the number of Class A-1 Options held by each Option Holder shall be reduced
proportionately so that the aggregate amount of Class A-1 Certificates callable
by the exercise of Class A-1 Options shall equal the outstanding Certificate
Principal Balance of outstanding Class A-1 Certificates after giving effect to
such partial redemption. The Option Agent shall make such adjustments to its
records as shall be necessary to reflect such reductions and shall notify each
Option Holder of such adjustments.

         Section 2.6. Expiration.

         The Class A-1 Options shall expire, and the right to exercise the Class
A-1 Options shall terminate, on the earlier to occur of (a) the termination of
the Trust Agreement, and (b) the liquidation of the Trust.

         Section 2.7. Mutilated, Destroyed, Lost or Stolen Class A-1 Call Option
Certificates.

         (a)      If (i) any Class A-1 Call Option Certificate that has been
mutilated is surrendered to the Option Agent, or the Option Agent receives
evidence to its satisfaction of the destruction, loss or theft of any Class A-1
Call Option Certificate, and (ii) there is delivered to the Option Agent such
security or indemnity as may be required by it to hold it harmless, then, in the
absence of notice to the Option Agent that such Class A-1 Call Option
Certificate has been acquired by a Protected Purchaser, the Option Agent shall
execute on behalf of the Certificateholders holding Class A-1 Certificates, and
shall authenticate and deliver, in exchange for or in lieu of any such
mutilated, destroyed, lost or stolen Class A-1 Call Option Certificate, a
replacement Class A-1 Call Option Certificate in respect of a like aggregate
Certificate Principal Balance of Class A-1 Certificates.

         (b)      If, after the delivery of a replacement Class A-1 Call Option
Certificate in respect of a mutilated, destroyed, lost or stolen Class A-1 Call
Option Certificate pursuant to Section 2.7(a), a Protected Purchaser of the
original Class A-1 Call Option Certificate in lieu of which such replacement
Class A-1 Call Option Certificate was issued exercises such original Class A-1
Call Option Certificate, the Option Agent shall be entitled to recover such
replacement Class A-1 Call Option Certificate from the Person to whom it was
delivered or any Person taking such replacement Class A-1 Call Option
Certificate from such Person to whom such replacement Class A-1 Call Option

                                       12
<PAGE>

Certificate was delivered or any assignee of such Person, except a Protected
Purchaser, and shall be entitled to recover upon the security or indemnity
provided therefor to the extent of any loss, damage, cost or expense incurred by
the Option Agent in connection with such exercise.

         (c)      In connection with the issuance of any replacement Class A-1
Call Option Certificate under this Section 2.7, the Option Agent may require the
payment by the holder of the Class A-1 Call Option Certificate of a sum
sufficient to cover any tax or other governmental charge that may be imposed in
relation thereto and any other reasonable expenses (including the fees and
expenses of the Option Agent) connected therewith.

         (d)      Any Class A-1 Call Option Certificate issued pursuant to this
Section 2.7 in replacement of any mutilated, destroyed, lost or stolen Class A-1
Call Option Certificate shall be entitled to all the benefits of this Agreement
equally and proportionately with any and all other Class A-1 Call Option
Certificates duly issued hereunder.

         (e)      The provisions of this Section 2.7 are exclusive and shall
preclude (to the extent lawful) all other rights and remedies with respect to
the replacement of mutilated, destroyed, lost or stolen Class A-1 Call Option
Certificates.

         Section 2.8. Representations and Warranties of UBS Securities.

         UBS Securities represents and warrants to the Depositor and the Option
Agent as of the date of this Agreement and as of the time of delivery of the
Class A-1 Call Option Certificates by the Option Agent to the Depositor that
each of the execution of this Agreement, and the grant of the Class A-1 Options
and the direction to the Option Agent to issue the Class A-1 Call Option
Certificates in the manner provided for in Section 2.1 of this Agreement, has
been duly authorized by UBS Securities and is within the corporate power and
authority of UBS Securities.

         Section 2.9. Representations and Warranties of the Depositor.

         The Depositor represents and warrants to UBS Securities and the Option
Agent as of the date of this Agreement and as of the time of delivery of the
Class A-1 Call Option Certificates by the Option Agent to the Depositor that
each of the execution of this Agreement and the receipt by the Depositor of the
Class A-1 Options, has been duly authorized by the Depositor and is within the
corporate power and authority of the Depositor.

                                       13
<PAGE>

                                  ARTICLE III

                                  OPTION AGENT

         Section 3.1. Limitation on Liability.

         The Option Agent shall be protected and shall incur no liability for or
in respect of any action taken, suffered or omitted by it in connection with its
administration of the Class A-1 Options in reliance upon any instrument of
assignment or transfer, power of attorney, endorsement, affidavit, letter,
notice, direction, consent, certificate, statement or other paper or document in
good faith believed by it to be genuine and to be signed, executed and, where
necessary, verified and acknowledged, by the proper Person or Persons.

         Section 3.2. Duties of Option Agent.

         The Option Agent undertakes only the specific duties and obligations
imposed under this Agreement upon the following terms and conditions, by all of
which the Depositor, each Option Holder and each Certificateholder shall be
bound:

         (a)      The Option Agent may consult with legal counsel (who may be
legal counsel for the Depositor or any of its Affiliates), and the opinion of
such counsel shall be full and complete authorization and protection to the
Option Agent as to any action taken or omitted by it in good faith and in
accordance with such opinion, provided the Option Agent shall have exercised
reasonable care in the selection by it of such counsel.

         (b)      Whenever in the performance of its duties under this
Agreement, the Option Agent shall deem it necessary or desirable that any fact
or matter be proved or established by the Depositor or the Trustee prior to
taking or suffering any action under this Agreement, such fact or matter may be
deemed to be conclusively proved and established by a Depositor Order or a
certificate signed by a Responsible Officer of the Trustee and delivered to the
Option Agent; and such certificate shall be full authorization to the Option
Agent for any action taken or suffered in good faith by it under this Agreement
in reliance upon such certificate.

         (c)      The Option Agent shall be liable under this Agreement only for
its own gross negligence, willful misconduct or bad faith.

         (d)      The Option Agent shall not be liable for or by reason of any
of the statements of fact or recitals contained in this Agreement or be required
to verify the same, but all such statements and recitals are and shall be deemed
to have been made by the Depositor only.

         (e)      The Option Agent shall not have any responsibility in respect
of and makes no representation as to the validity of the Class A-1 Options or
the execution and delivery of this Agreement (except the due execution of this
Agreement by the Option

                                       14
<PAGE>

Agent); nor shall it be responsible for any breach by the Trustee or any Option
Holder of any covenant or condition contained in this Agreement; nor shall it by
any act under this Agreement be deemed to make any representation or warranty as
to the Certificates or the Underlying Securities.

         (f)      The Option Agent is hereby authorized and directed to accept
instructions with respect to the performance of its duties under this Agreement
from the Chairman of the Board, the Chief Executive Officer, the Chief Financial
Officer, the Chief Operating Officer, the President, a Vice President, a Senior
Vice President, a Managing Director, the Treasurer, an Assistant Treasurer, the
Secretary or an Assistant Secretary of the Depositor, and to apply to such
officers for advice or instructions in connection with its duties, and it shall
not be liable for any action taken or suffered to be taken by it in good faith
in accordance with instructions of any such officer.

         (g)      The Option Agent and any shareholder, director, officer or
employee of the Option Agent may buy, sell or deal in any of the Class A-1
Options, the Class B-1 Options or the Certificates or otherwise act as fully and
freely as though it were not Option Agent under this Agreement, so long as such
persons do so in full compliance with all applicable laws and, to the extent
applicable, the Trust Agreement. Nothing in this Agreement shall preclude U.S.
Bank Trust National Association from acting in any other capacity for the Trust,
the Depositor or for any other legal entity.

         (h)      The Option Agent may execute and exercise any of the rights or
powers hereby vested in it or perform any duty under this Agreement either
itself or by or through its attorneys or agents.

         (i)      The Option Agent shall act solely as the agent of the
Certificateholders under this Agreement. The Option Agent shall not be liable
except for the failure to perform such duties as are specifically set forth in
this Agreement, and no implied covenants or obligations shall be read into this
Agreement against the Option Agent, whose duties shall be determined solely by
the express provisions of this Agreement.

         (j)      The Option Agent shall not be under any obligation or duty to
institute, appear in or defend any action, suit or legal proceeding in respect
of this Agreement, unless first indemnified to its satisfaction, but this
provision shall not affect the power of the Option Agent to take such action as
the Option Agent may consider proper, whether with or without such indemnity.
The Option Agent shall promptly notify the Depositor and the Trustee in writing
of any claim made or action, suit or proceeding instituted against it arising
out of or in connection with this Agreement.

         Section 3.3. Change of Option Agent.

         (a)      The Option Agent may resign and be discharged from its duties
under this Agreement upon thirty days' notice in writing mailed to the Depositor
and the Trustee by registered or certified mail, and to the Option Holders by
first-class mail at the expense of

                                       15
<PAGE>

the Depositor; provided that no such resignation or discharge shall become
effective until a successor Option Agent shall have been appointed under this
Agreement. The Depositor may remove the Option Agent upon three Business Days'
notice in writing, mailed to the Option Agent and to the Option Holders by
first-class mail; provided that no such removal shall become effective until a
successor Option Agent shall have been appointed under this Agreement.

         (b)      If the Option Agent shall resign or be removed or shall
otherwise become incapable of acting, the Depositor shall promptly appoint a
successor to the Option Agent. If the Depositor shall fail to make such
appointment of a permanent successor within a period of thirty (30) days after
such removal or within sixty (60) days after notification in writing of such
resignation or incapacity by the resigning or incapacitated Option Agent or by
the Option Holder, then the Option Agent or any registered Option Holder may
apply to any court of competent jurisdiction for the appointment of such a
successor.

         (c)      Any entity that may be merged or consolidated with or that
shall otherwise succeed to substantially all of the trust or agency business of
the Option Agent shall be deemed to be the successor Option Agent without any
further action.

         (d)      The Option Agent shall at all times be a bank that is not an
Affiliate of the Depositor (but may have normal banking relationships with the
Depositor or the Underlying Securities Issuer and their respective Affiliates),
that (i) is organized and doing business under the laws of any State or the
United States; (ii) is authorized under such laws to exercise corporate trust
powers; (iii) has a combined capital and surplus of at least $50,000,000; (iv)
is subject to supervision or examination by federal or state authority; and (v)
has (or has a parent that has) a long-term unsecured debt rating of at least
BBB- by Standard & Poor's Ratings Services, a Division of The McGraw-Hill
Companies, Inc., and at least Baa3 by Moody's Investors Service, Inc., or their
respective successors, if any. If the bank publishes reports of condition at
least annually, pursuant to law or to the requirements of the aforesaid
supervising or examining authority, then for the purpose of this Section 3.3(d),
the combined capital and surplus of such corporation shall be deemed to be its
combined capital and surplus as set forth in its most recent report of condition
so published. If at any time the Option Agent shall cease to be eligible in
accordance with the provisions of this Section 3.3(d), the Option Agent shall
resign immediately in the manner and with the effect specified in Section
3.3(a).

                                   ARTICLE IV

                                  MISCELLANEOUS

         Section 4.1. Remedies.

         The remedies of the Option Holder at law in the event of any default or
threatened default by a Certificateholder in the performance of or compliance
with any of the terms

                                       16
<PAGE>

of this Agreement are not and will not be adequate and, to the full extent
permitted by law and equity, such terms may be specifically enforced by a decree
for the specific performance of any agreement contained in this Agreement or by
an injunction against a violation of any of the terms of this Agreement or
otherwise.

         Section 4.2. Limitation on Liabilities of Option Holder.

         Nothing contained in this Agreement or the Class A-1 Options shall be
construed as imposing any obligation on any Option Holder to exercise any Class
A-1 Option or to purchase any of the Class A-1 Certificates.

         Section 4.3. Notices.

         All notices and other communications under this Agreement shall be in
writing and shall be delivered, or mailed by registered or certified mail,
postage prepaid, return receipt requested, or delivered by a nationally
recognized overnight courier, addressed (a) if to any Option Holder, at the
registered address of such Option Holder as set forth in the register kept by
the Option Agent pursuant to Section 2.4(e), or (b) if to the Option Agent, to
U.S. Bank Trust National Association, 100 Wall Street, Suite 1600, New York, New
York 10005, Attention: Corporate Trust, or to such other address of which the
Option Agent shall have given notice to the Option Holder and the Trustee, or
(c) if to the Trust or the Trustee, to the Corporate Trust Office specified in
the Trust Agreement, or (d) if to the Depositor, 445 Broad Hollow Road, Suite
239, Melville, New York 10171. Any such notice shall be effective on the
Business Day on which it is delivered in person, on the Business Day following
the date on which it is provided to a nationally recognized overnight courier
and on the fifth Business Day following the day on which it is deposited in the
mails, in each case as provided above. Subject to Section 2.2(a), the Option
Agent shall promptly forward to each Option Holder a copy of any notice or other
communication received by it under this Agreement.

         Section 4.4. Amendment.

         (a)      This Agreement may be amended from time to time by the
Depositor and the Option Agent without the consent of any Option Holder, upon
receipt of an opinion of counsel satisfactory to the Option Agent that the
execution of the amendment is authorized or permitted by this Agreement and all
conditions provided for in this Agreement relating to such amendment have been
complied with and that such amendment would not alter the status of the Trust as
a grantor trust under the Internal Revenue Code of 1986, for any of the
following purposes: (i) to cure any ambiguity or to correct or supplement any
provision in this Agreement that may be defective or inconsistent with any other
provision in this Agreement or to provide for any other terms or modify any
other provisions with respect to matters or questions arising under this
Agreement that shall not adversely affect in any material respect the interests
of any Option Holder or any holder of a Class A-1 Certificate or alter the terms
on which the Class A-1 Options are exercisable or the amounts payable upon
exercise of an Class A-1

                                       17
<PAGE>

Option or (ii) to evidence and provide for the acceptance of appointment under
this Agreement of a successor Option Agent.

         (b)      This Agreement may also be modified or amended from time to
time by the Depositor and the Option Agent with the consent of Option Holders
holding 662/3% of the Class A-1 Options, upon receipt of an opinion of counsel
satisfactory to the Option Agent that the execution of the amendment is
authorized or permitted by this Agreement and all conditions provided for in
this Agreement relating to such amendment have been complied with, for the
purpose of adding any provisions to or changing in any manner or eliminating any
of the provisions of this Agreement or the Class A-1 Options or modifying in any
manner the rights of the Option Holders; provided, however, that no such
amendment shall (i) adversely affect in any material respect the interests of
the holders of the Class A-1 Certificates without (x) the consent of all the
holders of the Class A-1 Certificates and (y) written confirmation from each of
the Rating Agencies that such amendment will not result in a downgrading or
withdrawal of its rating of the Class A-1 Certificates, if then rated by the
Rating Agencies; (ii) alter the terms on which the Class A-1 Options are
exercisable or the amounts payable upon exercise of an Class A-1 Option without
the consent of the holders of all the Class A-1 Certificates and all the Class
A-1 Options; or (iii) reduce or modify the vote required by clause (i) or (ii)
of this proviso without the consent of the holders of 100% of the Class A-1
Certificates. Notwithstanding any other provision of this Agreement, this
Section 4.4(b) shall not be amended without the consent of 100% of the Class A-1
Option Holders.

         (c)      Promptly after the execution of any amendment or modification
to this Agreement, the Option Agent shall furnish a copy of such amendment or
modification to each Option Holder, to the Trustee and to the Rating Agencies.
It shall not be necessary for the consent of the Option Holders or the Class A-1
Certificates to approve the particular form of any proposed amendment or
modification, but it shall be sufficient if such consent shall approve the
substance of such amendment or modification. The manner of obtaining and
evidencing the authorization of the execution of such consents shall be subject
to such reasonable regulations as the Option Agent may prescribe.

         Section 4.5. Governing Law.

         THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH
THE LAWS OF THE STATE OF NEW YORK.

         Section 4.6. Judicial Proceedings.

         Any judicial proceeding brought against any party with respect to this
Agreement may be brought in any court of competent jurisdiction in the County of
New York, State of New York or of the United States of America for the Southern
District of New York and, by execution and delivery of this Agreement or
acceptance of a Class A-1 Certificate, as applicable, each party (a) accepts,
generally and unconditionally, the nonexclusive jurisdiction of such courts and
any related appellate court, and agrees that

                                       18
<PAGE>

such party shall be bound by any judgment rendered thereby in connection with
this Agreement, subject to any rights of appeal, and (b) irrevocably waives any
objection that such party may now or hereafter have as to the venue of any such
suit, action or proceeding brought in such a court or that such court is an
inconvenient forum.

         Section 4.7. Nonpetition Covenant.

         Each of the Option Agent and each Option Holder agrees that it shall
not, until the date which is one year and one day after the payment in full of
all securities issued by the Trust, the Depositor or other trusts formed,
established or settled by the Depositor, acquiesce, petition or otherwise invoke
or cause the Trust, the Depositor, or any such other trust to invoke the process
of the United States of America or any State or other political subdivision of
the United States or any entity exercising executive, legislative, judicial,
regulatory or administrative functions of or pertaining to government for the
purpose of commencing or sustaining a case by or against the Trust, the
Depositor or any such other trust under a federal or state bankruptcy,
insolvency or similar law or appointing a receiver, liquidator, assignee,
trustee, custodian, sequestrator or other similar official of the Trust, the
Depositor or any such other trust or all or any part of the property or assets
of the Trust, the Depositor or any such other trust or ordering the winding up
or liquidation of the affairs of the Trust, the Depositor or any such other
trust.

         Section 4.8. No Recourse.

         Each of the Option Agent and each Option Holder agrees that it shall
not have any recourse to the Trust for any amounts due under this Agreement.
This Section 4.8 shall not affect any rights or remedies that an Option Holder
may have against the Option Agent or the Certificateholders hereunder.

         Section 4.9. New Issuances.

         The Depositor agrees that it shall not cause the Trust to issue
additional Certificates unless it obtains from the holders of such Certificates
options on substantially the same terms as the Class A-1 Options and the Class
B-1 Options, as the case may be, and either (x) it resells such options to the
then-current holders of the Class A-1 Options and the Class B-1 Options, in
proportion to their holdings of Class A-1 Options and Class B-1 Options, as
applicable, or to such Persons' designees, or (y) takes such measures as shall
be necessary to ensure that the issuance of such additional Certificates does
not impair the right of the holder of any Class A-1 Option to exercise such
Class A-1 Option on the terms set forth in this Agreement.

                                       19
<PAGE>

         IN WITNESS WHEREOF, the parties hereto have caused this Class A-1 Call
Option Agreement to be executed by their duly authorized officers as of the
first date specified above.

                              CORPORATE ASSET BACKED CORPORATION,
                              as sole initial Option Holder

                              By: /s/ Robert D. Vascellaro
                                  ----------------------------------------------
                                  Name: Robert D. Vascellaro
                                  Title: Vice President

                              UBS SECURITIES LLC

                              By: /s/ Jeff Blum
                                  ----------------------------------------------
                                  Name: Jeff Blum
                                  Title: Managing Director
                                         Global Head of Debt Syndicate

                              By: /s/ Michael Sabatino
                                  ----------------------------------------------
                                  Name: Michael Sabatino
                                  Title: Director
                                         Fixed Income Syndicate

                              U.S. BANK TRUST NATIONAL ASSOCIATION,
                              as Option Agent and Attorney-in-Fact for the
                              Certificateholders

                              By: /s/ David J. Kolibachuk
                                  ----------------------------------------------
                                  Name: David J. Kolibachuk
                                  Title: Vice President

<PAGE>

                                                                       EXHIBIT A

                              [Form of Call Notice]

                              CLASS A-1 CALL NOTICE

         To:      U.S. Bank Trust National Association, as Option Agent
                  100 Wall Street, Suite 1600
                  New York, New York 10005
                  Attention: Corporate Trust

         This Call Notice is delivered pursuant to the Class A-1 Call Option
Agreement, dated as of March 8, 2004 (the "Class A-1 Call Option Agreement"),
among Corporate Asset Backed Corporation, a Delaware corporation (the
"Depositor"), as the sole initial Option Holder, UBS Securities LLC, as the
initial purchaser from the Depositor, and initial and sole holder, at the time
of execution of the Class A-1 Call Option Agreement, of the Class A-1
Certificates, and U.S. Bank Trust National Association, a national banking
association, acting as Option Agent for the holders of Class A-1 Certificates
from time to time (the "Option Agent").

         The undersigned registered holder of ____ Class A-1 Options hereby
exercises _____ Class A-1 Options for the purchase of Class A-1 Certificates
upon and subject to the terms specified in the Class A-1 Call Option Agreement.

         Subject to the satisfaction of the conditions specified in the Class
A-1 Call Option Agreement, the Call Date in respect of the Class A-1 Options so
exercised shall be: ___________________ (which date shall be at least 15 days
after the date of delivery of this Call Notice or, if this Call Notice is
delivered with respect to any exercise of an Class A-1 Option pursuant to
Section 2.2(a)(ii) or 2.2(a)(iii), at least 2 Business Days after the date of
delivery of this Call Notice).

         The undersigned hereby agrees that (i) if the Call Option is being
exercised other than in connection with a tender offer, and the undersigned has
paid the Call Price to the Option Agent by 10:00 a.m. (New York City time) on
the Call Date, or (ii) in the case of a tender offer, if the Trustee has
received payment of the Call Price from the Underlying Securities Issuer or
other purchaser by 10:00 a.m. (New York City time) on the later of (A) the date
specified for settlement in the Call Notice, or (B) the earlier to occur of the
date immediately following the date on which the tender offer is consummated or
the date on which it expires unconsummated, the undersigned will have purchased
the Class A-1 Certificates deliverable pursuant to such Class A-1 Options at the
time such payment is made. The aggregate Call Price in respect of such Class A-1
Options shall be _________________) (insert number calculated in accordance with
the definition of "Call Price" in the Class A-1 Call Option Agreement).

<PAGE>

         The undersigned requests that the Underlying Securities deliverable in
exchange for the Class A-1 Certificates purchased in such exercise be
transferred to the following account in accordance with the following
instructions: __________________________________________
________________________________________________________________________________
________________________________________________________ (insert information
required for transfer of Underlying Securities).

                                       2

<PAGE>

         All capitalized terms used but not defined in this Call Notice shall
have the meanings assigned to such terms in the Class A-1 Call Option Agreement,
and this Call Notice is subject to the terms and conditions of that Agreement.

         Dated:

                                      [NAME OF OPTION HOLDER]

                                      By _______________________________
                                         Name:
                                         Title:

                                       3

<PAGE>

                                                                       EXHIBIT B

                         [Form of Transfer Confirmation]

                         CLASS A-1 TRANSFER CONFIRMATION

         This Transfer Confirmation is delivered pursuant to the Class A-1 Call
Option Agreement, dated as of March 8, 2004 (the "Class A-1 Call Option
Agreement"), among Corporate Asset Backed Corporation, a Delaware corporation
(the "Depositor"), as the sole initial Option Holder, UBS Securities LLC, as the
initial purchaser from the Depositor, and initial and sole holder, at the time
of execution of the Class A-1 Call Option Agreement, of the Class A-1
Certificates, and U.S. Bank Trust National Association, a national banking
association, acting as Option Agent for the holders of Class A-1 Certificates
from time to time (the "Option Agent").

         [Name of Transferor] (the "Transferor") and [Name of Transferee] (the
"Transferee") hereby instruct the Option Agent to register a transfer (the
"Transfer") of _________ [Must be whole number] Class A-1 Options on the books
of the Option Agent maintained for such purpose.

         As a condition to such Transfer, the Transferee hereby represents and
warrants to the Transferor, the Option Agent and the Trustee referred to in the
Class A-1 Call Option Agreement, for the benefit of the Trust referred to
therein, that:

                  (1) The Transferee acknowledges that the Class A-1 Options
         have not been and will not be registered under the Securities Act of
         1933, as amended (the "Securities Act"), or any state securities laws,
         and may not be offered or sold in the United States except in
         accordance with an exemption under the Securities Act.

                  (2) The Transferee is a "qualified institutional buyer" within
         the meaning of Rule 144A under the Securities Act;

                  (3) [With respect to any initial Transfer from the Depositor
         only: Such information regarding the Class A-1 Options, the Trust and
         the Class A-1 Certificates as the Transferee has required is, or has
         been made, available to it and it has been afforded the opportunity to
         ask questions and receive answers concerning the terms and conditions
         of the Class A-1 Options, and to obtain such additional information as
         the Transferor possesses or can acquire without unreasonable effort or
         expense that is necessary to verify the accuracy of such information;]

                  (4) The Transferee agrees that the Class A-1 Options may be
         offered, resold, pledged or otherwise transferred only (A) to a person
         who the seller reasonably believes is a "qualified institutional buyer"
         within the meaning of Rule

<PAGE>

         144A under the Securities Act that purchases for its own account or for
         the account of a qualified institutional buyer, pursuant to an
         exemption from registration under the Securities Act, and in compliance
         with applicable state securities laws, and (B) in compliance with the
         securities laws of each other applicable jurisdiction;

                  (5) Neither the Transferee, nor any person acting on its
         behalf, has offered the Class A-1 Options for sale, or solicited any
         offer to buy the Class A-1 Options by means of any form of general
         solicitation or general advertising, including but not limited to the
         methods described in Rule 502(c) under the Securities Act or in any
         other manner that would render the issuance and sale of the Class A-1
         Options a violation of the Securities Act or require registration
         pursuant to the Securities Act;

                  (6) The Transferee will notify, and cause each subsequent
         transferee of the Class A-1 Options to agree to notify, each subsequent
         holder of the Class A-1 Options of the restrictions referred to in
         paragraph (4) above.

         The address to which any notices addressed to the Transferee should be
addressed is as follows:_____________________________________.

         All capitalized terms used but not defined in this Transfer
Confirmation are used with the meanings specified in the Class A-1 Call Option
Agreement, and this Transfer Confirmation is subject to the terms and conditions
of that Agreement.

         This Transfer Confirmation shall be governed by and construed in
accordance with the laws of the State of New York.

         IN WITNESS WHEREOF, the parties have signed their names as of the date
set forth below.

                                        [NAME OF TRANSFEROR], as
                                        Transferor

                                        By _____________________________________
                                           Name:
                                           Title:

                                        [NAME OF TRANSFEREE], as
                                        Transferee

                                        By _____________________________________
                                           Name:
                                           Title:

                                       2

<PAGE>

                                        U.S. BANK TRUST NATIONAL
                                        ASSOCIATION, as Option Agent

                                        By _____________________________________
                                           Name:
                                           Title:

                                       3

<PAGE>

                                                                       EXHIBIT C

                               Option Certificate

                                       for

                                CLASS A-1 OPTIONS

                  relating to Class A-1 Certificates issued by
               CABCO SERIES 2004-1 TRUST (GOLDMAN SACHS CAPITAL I)

         THESE CALL OPTIONS HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
1933, AS AMENDED, AND MAY NOT BE TRANSFERRED, SOLD OR OTHERWISE DISPOSED OF
EXCEPT PURSUANT TO AN EXEMPTION UNDER SUCH ACT. THE CALL OPTIONS REPRESENTED
HEREBY MAY BE TRANSFERRED ONLY IN COMPLIANCE WITH THE CONDITIONS SPECIFIED IN
THE CALL OPTION AGREEMENT (AS DEFINED BELOW).

                             Class A-1 Call Options

                                [-] Call Options
  (Each Call Option relates to $25 principal amount of Class A-1 Certificates)

         No. O-[-]                                                        [Date]

         In connection with CABCO Series 2004-1 Trust (Goldman Sachs Capital I)
(the "Trust"), a trust created under the laws of the State of New York pursuant
to the Trust Agreement, dated as of March 8, 2004 (the "Trust Agreement"),
between Corporate Asset Backed Corporation, a Delaware corporation (the
"Depositor") and U.S. Bank Trust National Association, a national banking
association, as trustee (the "Trustee") and option agent, for value received,
this Option Certificate certifies that [-] or registered assigns, is entitled to
purchase, in whole or part, [-] 6.00% Class A-1 Certificates issued by CABCO
Series 2004-1 Trust (Goldman Sachs Capital I) on any Call Date designated by the
holder of these options (these "Call Options") at a purchase price equal to the
Call Price, all subject to the terms and conditions of the Class A-1 Call Option
Agreement, dated as of March 8, 2004 (the "Call Option Agreement"), among the
Depositor, as the sole initial Option Holder, UBS Securities LLC, as the initial
purchaser from the Depositor, and sole holder at the time of execution of the
Call Option Agreement, of the Class A-1 Certificates, and the Option Agent.

         Certain capitalized terms used in this Option Certificate are defined
in the Call Option Agreement and capitalized terms used but not defined herein
or therein shall have the respective meanings set forth in the Trust Agreement.

<PAGE>

         Each of (i) the Option Holder, by its acceptance hereof, and (ii) the
Option Agent agrees, that, without affecting any rights or remedies that the
Option Holder may have against the Option Agent or any Certificateholders under
the Call Option Agreement, it shall not have any recourse to the Trust for any
amount due under these Class A-1 Options.

                                          U.S.BANK TRUST NATIONAL
                                             ASSOCIATION,
                                             as Option Agent

                                          By:___________________________________

                                             Authorized Signatory

                                       2

<PAGE>

                               FORM OF ASSIGNMENT

         [To be executed only upon transfer of these Class A-1 Options]

         For value received, the undersigned registered holder of these Class
A-1 Options hereby sells, assigns and transfers unto _____________ ______ Class
A-1 Options [Must be whole number] to purchase Class A-1 Certificates, and
appoints _____ as such holder's Attorney to make such transfer on the books of
the Option Agent maintained for such purpose, with full power of substitution in
the premises. The undersigned hereby certifies that it has executed, together
with its transferee and the Option Agent, a Class A-1 Transfer Confirmation in
the form attached to the Class A-1 Call Option Agreement in connection with such
transfer.

         Dated:

         (Signature must conform in all respects to name of holder as specified
on the face of these Call Options)

                (Street Address)
         (City State) (Zip Code)

         Signed in the presence of:

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