Task: songer_casetyp1_7-3-1

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 - taxes, patents, copyright". 

PER CURIAM.
This is an action at law, brought in the federal District Court of Porto Rico, to recover taxes paid under protest. The plaintiff seeks to recover $8,000.13, that being the amount of taxes assessed under the Porto Rico Tax Act of August 20, 1925 (Acts Porto Rico 1925, No. 85), and paid under protest. The tax was assessed upon automobile tires and other articles manufactured by the plaintiff in the United States and imported into and sold by it in Porto Rico. In the District Court judgment was entered for the defendant, from which this writ was prosecuted.
We regard the questions presented as concluded by our decisions in Goodyear Tire & Rubber Co. v. Gallardo, Treas. (C. C. A.) 18 F.(2d) 926; Sanchez Morales & Co. v. Gallardo, Treas. (C. C. A.) 18 F.(2d) 550; and Porto Rico Tax Appeals (C. C. A.) 16 F. (2d) 545.
The judgment of the District Court of Porto Rico is affirmed, with costs to the defendant in error.

Question: What is the specific issue in the case within the general category of "economic activity and regulation - taxes, patents, copyright"?
A. state or local tax
B. federal taxation - individual income tax (includes taxes of individuals, fiduciaries, & estates)
C. federal tax - business income tax (includes corporate and parnership)
D. federal tax - excess profits
E. federal estate and gift tax
F. federal tax - other
G. patents
H. copyrights
I. trademarks
J. trade secrets, personal intellectual property
Answer:

Answer: A