When I decided that I would volunteer for the park clean-up project, I went about trying to convince my friends to do the same. I had not expected to meet with such resistance. My friends thought I was nuts to spend a Saturday cleaning up other people's trash. So, I went alone. Never in my wildest dreams did I realize what a rewarding experience this would be.

Which BEST describes the author's purpose for his reflective essay?
A. to describe a meaningful experience
B. to persuade readers to volunteer
C. to explain a decision-making process
D. to describe an opinion about volunteering