What follows is an opinion from a United States Court of Appeals.
Intervenors who participated as parties at the courts of appeals should be counted as either appellants or respondents when it can be determined whose position they supported. For example, if there were two plaintiffs who lost in district court, appealed, and were joined by four intervenors who also asked the court of appeals to reverse the district court, the number of appellants should be coded as six.
When coding the detailed nature of participants, use your personal knowledge about the participants, if you are completely confident of the accuracy of your knowledge, even if the specific information is not in the opinion. For example, if "IBM" is listed as the appellant it could be classified as "clearly national or international in scope" even if the opinion did not indicate the scope of the business. 

Your task concerns the first listed appellant. The nature of this litigant falls into the category "federal government (including DC)". Your task is to determine which category of federal government agencies and activities best describes this litigant.

Opinion:
COMMISSIONER OF INTERNAL REVENUE v. ROSENBLOOM FINANCE CORPORATION.
No. 5094.
Circuit Court of Appeals, Third Circuit.
Aug. 17, 1933.
Helen R. Carloss, Sewall Key and J. Louis Monarch, all of Washington, D. C. (C. M. Charest, Gen. Counsel, Bureau of Internal Revenue, and John D. Foley, Sp. Atty., Bureau of Internal Revenue, both of Washington, D. C., of counsel), for petitioner.
Wm. W. Spalding, of Washington, D. C. (Mason, Spalding & McAtee, of Washington, D. C., of counsel), for respondent.
Before BUFFINGTON, DAYIS, and THOMPSON, Circuit Judges.
BUFFINGTON, Circuit Judge.
The underlying question in this tax case is whether whisky warehouse certificates owned by the Rosenbloom Finance Corporation, the taxpayer, were acquired by gift from its majority shareholder, Sol Rosenbloom. If acquired by gift, their value for ascertaining profit was their cost to the donor, $51,538.26. If not so acquired, their cost to the taxpayer was $269,494.97. The Board of Tax Appeals held the transaction was not a gift, and the Commissioner took this appeal. There is no dispute as to facts, and the question is wholly one of law. The facts, a full discussion thereof, and citations of authorities bearing on the case are set forth at full length in the findings and opinion of the Tax Board, and by reference thereto we avoid useless restatement.
The taxpayer paid Rosenbloom no money, stock, or other consideration therefor. It was a voluntary transfer of property without consideration or compensation therefor, and the form it took involved no ownership by any third party, and, whatever form or semblance it took, in substance and reality it was a transfer with the aim of avoiding tax. In our judgment it was a gift. The decree of the Tax Board will therefore be set aside and the record remanded for due procedure in accord herewith.

Question: This question concerns the first listed appellant. The nature of this litigant falls into the category "federal government (including DC)". Which category of federal government agencies and activities best describes this litigant?

Choices:
cabinet level department
courts or legislative
agency whose first word is "federal"
other agency, beginning with "A" thru "E"
other agency, beginning with "F" thru "N"
other agency, beginning with "O" thru "R"
other agency, beginning with "S" thru "Z"
Distric of Columbia
other, not listed, not able to classify

Answer: 4