This question asks the following by citing a passage here below: "The statement [below], if true, most strongly support which one of the following?"
"The purpose of general theory of art is to explain every aesthetic feature that is found in any of the arts. Pre-modern general theories of art, however, focused primarily on painting and sculpture. Every pre-modern general theory of art, even those that succeed as theories of painting and sculpture, fails to explain some aesthetic feature of music"
(A) Any general theory of art that explains the aesthetic features of painting also explains those of sculpture.
(B) A general theory of art that explains every aesthetic feature of music will achieve its purpose.(C) Any theory of art that focuses primarily on sculpture and painting cannot explain every aesthetic feature of music.(D) No pre-modern general theory of art achieves its purpose unless music is not art.
(E) No pre-modern general theory of art explains any aesthetic features of music that are not shared with painting and sculpture.
I incorrectly answered (C), and I cannot understand why my choice is a trap. I am unconvinced that (D) is that answer because (C) clearly restates the logical conclusion that is supported by evidence. I suspect that the use of double-negatives is hampering my understanding of (D) as the correct answer, yet I still feel that (C) is more logical. Could you please help me understand what is at issue here?