7. If ϕ is a function, does a ϕ 1 = 1 for all a?( 1 ϕ a = 1 for all ... ...

If ϕ is a function, does a ϕ 1 = 1 for all a?

(1) 1 ϕ a = 1 for all a.

(2) a ϕ b = b ϕ a for all a and b.


(A) if statement (1) ALONE is sufficient to answer the question but statement (2) alone is not sufficient;
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Nova Press: Set B - Data Sufficiency Practice