Answer:
the answer B...................
Your circulatory system consists of your heart, blood vessels and blood, and is responsible for transporting life-giving oxygen throughout your body. When you exercise, your body's need for oxygen increases; the harder you work out, the more oxygen your body demands.
<span>Sixty percent of daily energy for the human body is determined by basal metabolism rate, or BMR. Basal metabolism rate is the minimum energy needed for a body to function (i.e. how many calories you would burn resting for an entire day and night).</span>
