Question

a fable about a lion and a mouse teaches the lesson \even the smallest friends can make a big difference.\ this is an example of: central idea; theme; supporting detail; main idea

Explanation:

The theme of a story is the underlying message or lesson it conveys. The fable of the lion and the mouse here has the lesson "Even the smallest friends can make a big difference", which is the theme. Central idea and main idea are more about the overall point of the story's content, and a supporting detail would be a part that backs up the main idea, not the lesson itself.

Answer:

B. Theme