What follows is an opinion from a United States Court of Appeals. Your task is to identify the federal agency (if any) whose decision was reviewed by the court of appeals. If there was no prior agency action, choose "not applicable".

Opinion:
Walter Francis John SHELLEY, Petitioner, v. RAILROAD RETIREMENT BOARD, Respondent.
No. 12411.
United States Court of Appeals Ninth Circuit.
Nov. 9, 1950.
Myles F. Gibbons Gen. Coun., David B. Schreiber, Associate Gen. Coun., Chicago, 111. (Louis Turner, Ben Diamond, Attorneys, R. R., Ret. Bd., Chicago, 111., of counsel), for respondent.
Before STEPHENS, BONE and ORR, Circuit Judges.
PER CURIAM.
It appearing that the petition for review ■in this case is based upon a decision of an intermediate administrative body entitled Appeals Council and not upon an order of the United States Railroad Retirement Board which is an independent agency in the executive branch of the United States Government, Section 10(a) Railroad Retirement Act 1937, 50 Stat. 314, 45 U.S.C.A. § 228j(a), and it further appearing that review can be had only from a decision of the Board the proceeding must be and is dismissed.
Petition dismissed.

Question: What federal agency's decision was reviewed by the court of appeals?

Choices:
Benefits Review Board
Civil Aeronautics Board
Civil Service Commission
Federal Communications Commission
Federal Energy Regulatory Commission
Federal Power Commission
Federal Maritime Commission
Federal Trade Commission
Interstate Commerce Commission
National Labor Relations Board
Atomic Energy Commission
Nuclear Regulatory Commission
Securities & Exchange Commission
Other federal agency
Not ascertained or not applicable

Answer: 13