The answer to this question is A: The first and last paragraphs.
So B would not be the answer because the character's name is just information about the person involved. 99.9% in cases, the author is not making any kind of point by just giving a name. So it's is not the main idea of a text.
C is not the answer because that is probably not going to have anything to do with the text unless it's about the author. That would be background information about the author you are reading about, but not the main idea.
D is not the answer because the vocabulary is not going to be important to be the main idea about a text. It's just going to be words you may not have already seen/know.
Therefore the only suitable answer to this question is A.
