HELP ME ILL GIVE YOU 40 POINTS JUST HELP M What causes blood pressure?
A. the strength of the muscles in the walls of the capillaries
B. the speed at which oxygen is returned to blood in the lungs
C. the force with which the ventricles contract
D. the rate at which blood flows through the heart

C

Explanation:

What causes blood pressure?

C

To pump blood around the body, the heart contracts and then relaxes through the cardiac cycle. The cycle begins with the contraction of the two atria, which push blood into the ventricles. Then, the ventricles contract, which forces the blood out of the heart.

When the heart pushes blood around the body during systole, the pressure placed on the vessels increases. This is called systolic pressure.

When the heart relaxes between beats and refills with blood, the blood pressure drops. This is called diastolic pressure.