Red blood cells pick up oxygen in the lungs. Blood travels away from the heart and lungs through the arteries. Red blood cells drop off oxygen to the cells through tiny tubes called capillaries. Blood then returns to the heart through the veins and the cycle begins again.
Nodding your head would be the right answer. hoped this helped!!:-)
B. blood pressure, thats why the doctors say to stay stress free cuz it can kinda kill you.
