The answer is: optimum pitch
Which statement best expresses the central idea of the passage
I believe this depends solely on personal preference. A work of literature that you like may not be good to somebody else, so the way you feel about something makes it either good or bad. I believe I am pretty comfortable determining the quality of literature given that I have read a lot of books and have an overall grasp of each literary era throughout history. It can be easy to critique a text if you are knowledgeable enough about that particular era, style of writing, and general context, but it could also be quite difficult depending on the topic of that work.
The answer is A inability to act
