If an idea is restated in a nonfiction article, what does this most likely signal for the reader?
what the author expects the reader to misunderstand
the least important but most complex detail
an error the author needs to correct for clarity
something the reader should think, feel, or do

I believe that the answer is "something that the reader should think, feel, or do". I believe this because it makes the most sense for one and two when an author is restating an idea it means it is important and they want the reader to feel that it is important too. The author also might want the reader to have emotions toward the idea depending on what it is. I hope I am not too late to answering this question.

discrimination! they faced a lot of racism