Your topic sentence should guide the rest of the information in the paragraph - think of it like a thesis statement - because it answers the question/prompt and describes the order at which you will discuss the topics in you paragraph. Therefore, it is the most important element.
Society has different viewpoints because the society most likely has never seen something or something about someone before and they are going to think differently about them
The logical fallacy that Jane makes in her response to Fran is red herring. This is because her response is deliberately diverting the conversation away from what Fran is saying.