Task: songer_casetyp1_7-2

What follows is an opinion from a United States Court of Appeals.
Your task is to identify the issue in the case, that is, the social and/or political context of the litigation in which more purely legal issues are argued. Put somewhat differently, this field identifies the nature of the conflict between the litigants. The focus here is on the subject matter of the controversy rather than its legal basis.
Your task is to determine the specific issue in the case within the broad category of "economic activity and regulation". 

PER CURIAM.
The sole question presented to this court in this case, namely, whether the Postmaster General of the United States is an indispensable party to a suit of this nature, has been heretofore decided by this court, and the question is no longer open to dispute. We held, in Neher v. Harwood, Postmaster, etc., 9 Cir., 128 F.2d 846, 852, that the Postmaster General was an indispensable party in an action to enjoin a postmaster from carrying into effect a “fraud” order issued by the Postmaster General under 39 U.S. C.A. § 259.
Accordingly, the order of the court below is affirmed.

Question: What is the specific issue in the case within the general category of "economic activity and regulation"?
A. taxes, patents, copyright
B. torts
C. commercial disputes
D. bankruptcy, antitrust, securities
E. misc economic regulation and benefits
F. property disputes
G. other
Answer:

Answer: E