Answer:
A. It describes one of the benefits of staying involved in scouting.
Step-by-step explanation:
The central idea (also called the main or key idea) of a text is the main point its author is making.
The central idea of the given text is that scouting gets even better with age. The narrator tells about the perks of staying involved in scouting throughout high school: scouts go on longer camping trips, learn more skills, get to teach younger scouts, and can get a college scholarship. Getting a scholarship is a benefit that you get only if you stay involved in scouting longer than most kids do.
This is why the correct option is A.