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)", specifically "other agency, beginning with "F" thru "N"". Your task is to determine which specific federal government agency best describes this litigant.

Opinion:
NATIONAL LABOR RELATIONS BOARD, Petitioner, v. INTERNATIONAL SHOE CORPORATION OF PUERTO RICO, Respondent.
No. 6599.
United States Court of Appeals First Circuit.
Heard Feb. 9, 1966.
Decided March 8, 1966.
Warren M. Davison, Attorney, Washington, D. C., with whom Arnold Ordman, General Counsel, Dominick L. Manoli, Associate Gen. Counsel, Marcel Mallet-Prevost, Asst. Gen. Counsel, and Clarice R. Feldman, Attorney, Washington, D. C., were on brief, for petitioner.
George L. Weasler, Santurce, P. R., for respondent.
Before ALDRICH, Chief Judge, and MARIS and COFFIN, Circuit Judges.
By designation.
PER CURIAM.
The National Labor Relations Board has petitioned this court to enforce its order directing International Shoe Corporation of Puerto Rico to bargain in good faith with Sindicato Obrero Insular, the union which on June 28, 1963 was certified after an election as the collective bargaining agent of the Corporation’s production and maintenance employees at its Manatí plants. The Corporation engaged in collective bargaining with the union for a period of about ten months after that date, but on June 24, 1964 declined to negotiate further with the union on the stated ground that it had filed the charges with the Board which later became the basis for the order here sought to be enforced.
The Corporation asserts a number of defenses against the enforcement of the order, all of which we have carefully considered and find to be without merit. It is sufficient to say that it is settled law that, absent unusual circumstances which we do not find present here, an employer is required to bargain with the certified representative of its employees for the full period of one year after certification, if that much time is necessary to reach agreement. And this is required even though the union loses its majority during the year through no fault of the employer. Brooks v. N. L. R. B., 1954, 348 U.S. 96, 75 S.Ct. 176, 99 L.Ed. 125; N. L. R. B. v. United States Sonics Corporation, 1 Cir. 1963, 312 F.2d 610. Moreover the filing by the union of a charge of unfair labor practices does not relieve the employer of his duty to bargain collectively. N. L. R. B. v. Harris, 5 Cir. 1953, 200 F.2d 656; N. L. R. B. v. Taormina Co., 5 Cir. 1953, 207 F.2d 251; N. L. R. B. v. Kit Manufacturing Company, 9 Cir. 1964, 335 F.2d 166, 167, cert. den. 380 U.S. 910, 85 S.Ct. 894, 13 L.Ed.2d 797.
A decree enforcing the order of the Board will be entered.

Question: This question concerns the first listed appellant. The nature of this litigant falls into the category "federal government (including DC)", specifically "other agency, beginning with "F" thru "N"". Which specific federal government agency best describes this litigant?

Choices:
Food & Drug Administration
General Services Administration
Government Accounting Office (GAO)
Health Care Financing Administration
Immigration & Naturalization Service (includes border patrol)
Internal Revenue Service (IRS)
Interstate Commerce Commission
Merit Systems Protection Board
National Credit Union Association
National Labor Relations Board
Nuclear Regulatory Commission

Answer: 9