What is the topic sentence? what is the subject of the topic sentence? what is the controlling idea of the topic sentence? which sentences in the paragraph do not support or prove the controlling idea?

The topic sentence is a sentence that expresses the main idea of the paragraph in which it occurs. The subject of the topic sentence is (a) the topic itself and (b) the controlling idea. The sentence(s) in the paragraph that do not support or prove the controlling idea is the topic sentence; the topic sentence is the main focus, the controlling idea is your opinion about the topic {sentence}.

My answer is b but i dont know if im right