Thanks for the question! Answer choice (A) actually would not be correct, even if the word “enjoys†were swapped out for “increase enjoyment†in the way you seem to be suggesting. A problem with (A) is that it it would read that “virtually any†novel written by a novelist the book reviewer trusts would increase the enjoyment of the book reviewer of that novel. This, however, isn’t true. If we look at the stimulus, we’re told that trust increases the book reviewer’s enjoyment of GOOD novels, not just any novels. It’s possible that the novelist produces mainly bad novels, and so then the trust the author feels wouldn’t necessarily increase her enjoyment of those novels, and so it would be untrue that virtually all novels written by the trusted novelist would have their enjoyment increased by the trust.
Hope this helps! Feel free to ask any other questions that you might have.