How does using a quotation add credibility to a writer’s ideas?

It makes the writing much more exciting and interesting.
It provides a contrast to the writer’s point of view.
It allows readers to put themselves in the writer’s place.
It strengthens a writer’s ideas and proves them more believable.

Which excerpt from leo tolstoy's the death of ivan ilyich reflects the author's opinion that the members of the medical profession don't really care about their patients?

If music be the food of love, play on; give me excess of it, that, surfeiting, the appetite may sicken, and so die. that strain again! it had a dying fall: o, it came o'er my ear like the sweet sound, that breathes upon a bank of violets, stealing and giving odour! now read the excerpt from "the love song of j. alfred prufrock." for i have known them all already, known them all: have known the evenings, mornings, afternoons, i have measured out my life with coffee spoons; i know the voices dying with a dying fall beneath the music from a farther room. what does the phrase "dying fall" most likely mean in both excerpts

Which best completes the list of brainstorm ideas?