What. is true about the way this passage presents information? Check all that apply

quite an interesting way to teach topic sentences, because the answer to this question is the best definition of a topic sentence that one can present, it is as if answering the questions taught you how to do it, this is some real teaching, it is terribly well-done.

the topic sentence in this paragraph is:

topic sentences writers stay on track and keep a paragraph from becoming an aimless collection of sentences about an idea.

which incidentally tells you what a topic sentence should be.

i think it's either 'to expose the corruption of the communists in russia', or 'to criticize animal brutality by communists in russia.'  

hope this ! : )