Use the Following Information to Answer Following Questions

Use the following information to answer Following Questions . A 50-year-old man has a body weight of 110 kg, resting heart rate of 90 beats/min, arterial pressure of 120/70 mm Hg, arterial hematocrit of 35% and a normal body temperature. His pressure-volume diagram of the left ventricle is shown below.
-What event occurs at point D in the pressure-volume relationship?

A) Atrioventricular valves close
B) Aortic valve opens
C) Aortic valve closes
D) Atrioventricular valves open
E) Third heart sound