How will the right answer fit in terms of support and conclusion?

Only the right answer will add support for disagreeing with the conclusion.

Highlight the main conclusion in the passage, if there is one:

Winchester would better meet its residents’ needs by closing its small branch libraries and opening one larger, well-supplied library.

[SUPPORT]. However, [SUPPORT]. Thus, [CONCLUSION].

The conclusion all of a sudden brings in “residents’ needs” when that hadn’t been mentioned anywhere else. When the author changes the subject like that, the right answer will call them out for it. I’d expect to see info that says the big library might not meet resident’s needs.

Map the wording of the answers to the wording of the passage:

(A) Many Winchester residents never use the branch libraries…

Cool story, but the conclusion is about the “large library”. This doesn’t get anyone to disagree that the big library would be better.

(B) Most Winchester residents have complained about the selection…

Same as (A), more negative info about the “branch libraries” doesn’t support disagreeing that the big library will be better.

(C) The only possible site for a new library is not readily accessible…

The test expects you to recognize that “not readily accessible” means it won’t meet their needs. It’s the “only” option, and it impacts “most” residents, so that definitely supports disagreeing with the conclusion that wants the big library.

(D) It would cost Winchester a significant amount of money…

Don’t get distracted. This isn’t about why the “large library” is a bad plan in an overall way, only about whether it will “better meet its residents’ needs”. An answer about “cost” doesn’t map well to that wording at all.

(E) …attempts to cater to the tastes of the residents…

Wow, who cares? If you’re picking this you must be adding in at least a couple steps of your own reasoning to connect this to the argument. In which case I’d say you’re misunderstanding what this test is asking you to do.

(C) is the correct answer.

Common pattern/s in this question: Pick more winners and eliminate more losers quickly by recognizing whenever an author changes the subject. Valid conclusions can’t bring in new stuff the rest of the passage never talks about.