The correct answer is C) listing.
One way in which brainstorm compare-and-contrast topic ideas is by listing.
When a group of people does a brainstorming session, they want to get as many possible ideas in order to get a couple of them, and then make a decision. This technique is a good one to compare-and.contrast topic ideas because you get lists that allow you to make comparisons and clearly see which ones serve and are good and what are not. A good list helps people in the decision-making process.