Which best describes a topic sentence?

• A. States the subject of the paragraph.
• B. Provides the final conclusion.
• C. Offers a detailed example.
• D. Lists the supporting details.

Answer: (A)

A topic sentence introduces what the paragraph will be about. It states the subject or main idea the paragraph will focus on, giving the reader a clear sense of the direction and purpose of the whole paragraph. Because readers rely on that opening line to know what’s coming, the topic sentence is placed at the start and shapes the rest of the sentences that follow.

Think of a paragraph about how sunlight helps plants grow. The topic sentence would name that focus, such as “Sunlight is essential for plant growth,” and the sentences that follow would provide evidence—like how sunlight powers photosynthesis, why plants need the right amount of light, and what happens if light is scarce. The final conclusion, specific examples, or lists of details are all ways the paragraph can develop or support that idea, but they don’t itself name the topic—that’s what the topic sentence does.