Hey there! I'm happy to help! :D
A normal composition is made up of three main parts: the introduction, the body, and the conclusion.
The introduction is the beginning that hooks the reader and introduces the talking points.
The body is the main part that elaborates a lot and is filled with detail. The main content of the composition is found here.
The conclusion is what summarizes wraps up the composition.
We want to find out which answer option describes the body.
Answer A is talking about the introduction, not the body.
Answer B is what the body does: it supports, explains, and elaborates on the thesis, which is another word for the theme or main point of the composition.
Answer C is talking about the conclusion, not the body.
Answer D is talking about the introduction, because that is where the attitude or opinion is established.
Therefore, the answer is b. supports, explains, and elaborates on the thesis.
I hope that this helps! Have a wonderful day!