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.
The underlying question in this ease was the validity of tile patent involved’ because of the novelty of its alleged invention. No principles of law are involved.
The court below discussed the questions involved with unusual detail and thoroughness in an exhaustive opinion. The court has had the benefit of an equally thorough presentation of the ease by counsel for plaintiff in oral argument and comprehensive brief, but such presentation and our own study of the record fails to convince us the trial judge was in error. In view of his able opinion, and finding ourselves in accord therewith, we adopt it as expressive of our view and limit ourselves to affirming the deeree based upon it.

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: G