which one of the following statements about a topic sentence and a main idea is accurate? a. a topic sentence does not change position, but the main idea can be found in multiple places.   b. a topic sentence is found in the introduction, while a main idea is found in the conclusion.   c. a topic sentence is the central idea of a paragraph, while a main idea is the central idea of an entire text.   d. a topic sentence and a main idea are always the same thing.