Part b: what quotation from the essay directly supports the overall purpose in part a?

In order to answer this question, you must determine what the overall purpose of Part A is.  What is the central idea, or what is talked about the most?  This would be more of an opinionated statement that has supporting details within both Parts A and B.  Once you know that, you can then find a quote in Part B that supports what you choose as the overall purpose.

compare & contrast informative essay/speech

when speaking or writing for the sole purpose of providing information in order to give audience members a good basis for making a decision, you would present an informative speech or essay.   because you wouldn’t want to be persuading the audience by arguing for one type of exercise over the other, you wouldn’t choose a persuasive/argumentative technique.   to fairly, and without bias, present information about the pros and cons of each type exercise, a compare/contrast, informative speech/essay would be the best bet.