Which of the events below does not occur when the semilunar valves are open?
a. ventricles are in systole
b. av valves are closed
c. blood enters pulmonary arteries and the aorta
d. ventricles are in diastole

The answer is A: ventricles are in systole

Explanation:

When the ventricular contraction begins for the outflow of blood to the great vessels, an increase in intraventricular pressure occurs, when it exceeds the pressure of the aorta on the left side and the pulmonary on the right, it results in the opening of the semilunar valves giving rise to the ejection of blood from the heart until the ventricles begin to relax. subsequently the valves are closed and another period of relaxation begins.

answer:

its probable on the floor if it fell off.