Comprehension questions are not memory questions. The passage contains every answer; the skill is finding it, not knowing it beforehand. Read for structure first: what is the author's main claim, and how is it supported?
Worked example: a passage argues that libraries survive because they offer quiet study space and expert help, not merely books. A question asks for the main idea. The option "libraries lend books" is true but too narrow; the option "libraries are closing" contradicts the passage; the main idea is the option that covers the whole argument: libraries survive by offering space and help beyond books. The best option covers the passage, not one sentence of it.