The correct answer is B.Sometimes people are capable of doing more than they realize.
Explanation:
An Unlikely Heroine was written by Elizabeth Kibler. And the implicit main idea in this part is that people are sometimes capable of doing more than they expect or realize. Terese wanted to drop out from the basketball team, but she realized that she had some abilities which she did not know she had and at the end, she was able to coach the team she wanted to drop out before.