If you are looking for a sentence in that paragraph to support the main idea, I think it would be "All it requires is a good pair of sneakers-no cables, stylish outfits, or weights required. The main idea is basically that walking is a good and easy way to begin exercising, and that explains it.
The correcy answer is B) wealthy.
The answer to your question is C. a, a, a, a, b, c, c, c, b. I hope this helps!
