The answer is C, because you want to make sure the readers know what you're talking about in your introduction, If you're going to summarize the story, you're either doing an actual summary or you're going to do it quite a bit earlier than the end. Just think about it in terms of a normal conclusion.
The author's main purpose was the explain that the Community Service Council was effectual to high school students. The personal backstory was to add more evidence of the effectiveness.
