Which of the following statements about pulmonary blood flow is most accurate?

A. During systole, the pressure in the pulmonary artery is essentially equal to the pressure in the right ventricle.

B. Blood flow through the lungs is significantly lower compared to cardiac output

C. the value of the mean pulmonary arterial pressure is about 25 mmHg

D. when the concentration of oxygen in the alveoli decreases below normal the adjacent blood vessels dilate

E. none of the answers