Wow, this one is engendered quite a lot of controversy.
There is definitely a clear answer though, which is
(D). And that the wrong answers are incorrect is equally clear (at least I hope my explanation makes it seem that way
.)
So let's dissect this monster by asking: What is the core of the argument?
European music is sophisticated because it can stand on its own. That is European music can be divorced from its context (rituals, social functions, etc.) and still make sense.
An answer that would be incompatible with the argument would suggest that
1) European music cannot stand on its own but must be understood in the context of its function
2) A certain kind of music can stand on it's own but is not sophisticated.
3) Music that is sophisticated cannot stand on its own - i.e., it is unintelligible.
1) is too direct and obvious (at least for a 700+ question), and doesn't touch on sophistication. A possible answer choice would be something like:
(F) Most people who are exposed to western music for the first time find it unintelligible2) mentions sophistication and would more likely be a GMAT answer choice. However, none of the answer choices (A - E) fall into this category. A hypothetical answer that fits into this category is:
(G) African griot music, understood by those who have no idea of the social function of the music, is a simple and unadorned. 3) This is the most subtle of the three. Essentially, we are saying that A = B (sophisticated music is intelligible) and are challenging this with an answer choice that says A does not equal B (sophisticated music is unintelligible). The answer choice that clearly speak to this is answer (D):
(D) Music that is unintelligible when it is presented independently of its original function tends to be the most sophisticated music. ANSWER
(A) African music has had a more powerful impact on the world than European music has had.
The argument says that European music has had a powerful impact. That African music has had the most impact does not undermine the previous statement. (B) European military and economic expansionism partially explains the global influence of European music.
The prompt begins with the words, [i]one reason why... Thus, it is not saying that European music's global influence has only one cause. [/i]
(C) The original functions of many types of Chinese music are no longer their defining forces.
This answer choice doesn't speak to sophistication, intelligibility or even global influence. It simply states that Chinese music is defined by something different than its original function. (D) The Answer(E) Some works of art lose their appeal when they are presented to serve a function other than their original one.
This answer choice would be much stronger if it replaced, Some works with Most European music. In fact, think back to 1) at the beginning of the post. Remember how I said that answer choice is the most obvious one. Well, (E) baits us into thinking that it is the same as 1). But by dropping in 'some works of art' it becomes too broad. Indeed 'some works of art' does not, by definition, include European music. So this answer choice can be said to be out of scope. Hope that helps