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:
NATIONAL LABOR RELATIONS BOARD, Petitioner, v. PERKINS MACHINE COMPANY, Respondent.
No. 6182.
United States Court of Appeals First Circuit.
Jan. 23, 1964.
Peter M. Giesey, Washington, D. C., Atty., with whom Arnold Ordman, Gen. Counsel, Dominick L. Manoli, Assoc. Gen. Counsel, Marcel Mallet-Prevost, Asst. Gen. Counsel, and Solomon I. Hirsh, Washington, D. C., Atty., were on brief, for petitioner.
John H. Goewey, Worcester, Mass., with whom James S. Gratton and Bowditch, Gowetz & Lane, Worcester, Mass., were on brief, for respondent.
Before WOODBURY, Chief Judge, and HARTIGAN and ALDRICH, Circuit Judges.
PER CURIAM.
Respondent employer was found to have violated sections 8(a) (5) and (1) of the National Labor Relations Act by refusing to furnish the union with certain wage information and data (allegedly relevant to a grievance and/or arbitration proceeding) during the term of a collective bargaining contract which, unlike respondent’s previous agreement, had no express provision imposing such an obligation. Such an obligation, however, is normally implied as part of an employer’s general duties under the act, cf. Boston Herald-Traveler Corp. v. N. L. R. B., 1 Cir., 1955, 223 F.2d 58, and an employer cannot refuse unless there has been a “clear and unmistakable” waiver by the union. Timken Roller Bearing Co. v. N. L. R. B., 6 Cir., 1963, 325 F.2d 746; N. L. R. B. v. Item Co., 5 Cir., 220 F.2d 956, 958-59, cert. den. 350 U.S. 836, 76 S.Ct. 73, 100 L.Ed. 746; Tide Water Associated Oil Co., 1949, 85 N.L.R.B. 1096, 1098. In finding that the omission of the previous affirmative clause from the present agreement following negotiations during which respondent said it would not grant such rights was not such a waiver, the Board erroneously referred to statements (in our opinion ambiguous, at best) made by the union after the agreement had been entered into, and hence entirely immaterial. Nevertheless, we cannot say the Board’s decision was without substantial support. Where a provision would normally be implied in an agreement by operation of the act itself (but cf. Speidel Corp., 1958, 120 N.L.R.B. 733, when it is not), we think a waiver should be express, and that a mere inference, no matter how strong, should be insufficient. Cf. Timken Roller Bearing Co. v. N. L. R. B., supra. It is not necessary, to support the Board, for us to follow the case it now cites of N. L. R. B. v. Gulf Atlantic Warehouse Co., 5 Cir., 1961, 291 F.2d 475. We could not agree with the seeming suggestion in that opinion that the parol evidence rule required the waiver to be contained within the four corners of the written agreement. Cf. Rodriguez v. Secretary of the Treasury of Puerto Rico, 1 Cir., 1960, 276 F.2d 344, 349. Nor has this been the Board’s position. Speidel Corp., supra; Berkshire Corp., 1959, 123 N.L.R.B. 685.
A decree will be entered enforcing the order of the Board.

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