Which function do capillaries serve in the cardiovascular system? (a) carry blood to the brain. (b) return blood to the lungs. (c) control body temperature. (d) replace blood cells.

Its B hope it helps.

C. helps control body temperature

Explanation:

the more fit you are, the faster the recovery. your heart rate drops most sharply in the first minute after you stop exercising; it should then fall about 20 beats a minute—a drop of less than 12 beats a minute is considered abnormal. this “recovery heart rate” is measured as part of an exercise stress test.