I'm not sure whether this is a question designed for the GMAT but let's see what we can find here anyway. Before we begin, though, it might be interesting to consider the WHETHER OR NOT part of the passage. In effect, I daresay, it nullifies anything that comes before it and you could perhaps literally only read what comes after it to answer the question.
Many artists claim that art critics find it is easier to write about art that they dislike than to write about art that they like. Whether or not this hypothesis is correct, most art criticism is devoted to art works that fail to satisfy the critic. Hence it follows that most art criticism is devoted to works other than the greatest works of art.
The conclusion above is properly drawn if which one of the following is assumed
(A) No art critic enjoys writing about art works that he or she dislikes intensely.
The usage of NO makes this assumption quite extreme. Even in the passage it's all about most and many etc.
(B) All art critics find it difficult to discover art works that truly satisfy them.
Another extreme claim. For reasons similar to (A) cut this one.
(C) A work of art that receives extensive critical attention can thereby become more widely known than it otherwise would have been.
Irrelevant. Whether or not some work of art becomes widely known isn't necessary for the argument to work.
(D) The greatest works of art are never recognized as such until long after the time of their creation.
I didn't spend much time on this, but this might be the answer choice that trips up those who begin to create stories. If you find yourself doing so, yellow flag it and move on.
(E) The greatest works of art are works that inevitably satisfy all critics.
Yes. The whole point in the argument is that most critics review things they dislike only. But for a great work of art to not be reviewed that would require ALL critics to not dislike it (according to the argument). Critic A, B, and C may dislike a great work of art, but that does not mean that Critic D, E, and F feel the same way. Those latter critics may therefore review the work of art (since they like it). If you negate this answer choice the argument crumbles.
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