B) it helps you serve others which makes you feel good
To prevent injuries, because if you are running around and exercising, if you haven't warmed up, you could pull a muscle or injure yourself. Cool downs help calm your body down and lower your heart rate.
I would go with A) or the first option because wearing a hat is not used in exercise, not C) because wearing stuff heavier than yourself wont let u move right, and B) just doesn't sound right.
