What is the difference between the main idea and the supporting details?

• A. Main idea is a detail; supporting details provide evidence.
• B. The main idea is the central point.
• C. Main idea is the central point; supporting details provide evidence.
• D. Main idea is the author's tone; supporting details are unrelated.

Answer: (C)

The main idea is the central point or claim the author wants you to take away, while the supporting details are the facts, examples, reasons, and descriptions that back up that point and show why it’s true. The main idea sets the overall message; the details fill it in and make it convincing.

For instance, if a paragraph argues that regular exercise improves mood, the main idea is that exercise boosts mood. The details would include things like studies showing mood benefits, examples of how a workout can lift spirits, and explanations of mechanisms (like endorphins) that connect activity to mood changes.

That’s why this choice is the best: it separates the central message from the evidence that supports it. It’s not a detail, and it isn’t about the author’s tone or an unrelated element. The supporting details only matter because they reinforce the central point.