Which statement best distinguishes a central idea from a topic?

• A. The topic is the subject; the central idea is the main point the author makes about that subject.
• B. The central idea and topic are the same.
• C. The topic is about details; the central idea is about grammar.
• D. The central idea is a list of facts; topic is the subject.

Answer: (A)

The main idea being tested is how to tell the difference between a topic and the central idea. The topic is the subject of the passage—the broad thing being discussed. The central idea is the main point the author makes about that subject—the key message or argument the author wants you to take away.

For example, if a passage is about smartphones, the topic might be smartphones in daily life, but the central idea would be the author’s specific point about what smartphones do for communication or how they change our behavior. So the statement that the topic is the subject and the central idea is the main point the author makes about that subject is exactly what distinguishes them.

Saying the central idea and the topic are the same isn’t right because they serve different roles: one naming the subject, one naming the author’s main point about that subject. Describing the topic as about details and the central idea as about grammar misses the core relationship entirely. And thinking the central idea is a list of facts isn’t accurate—the central idea is a single, supported point the author emphasizes about the topic.