During Systole, the arterial pressure is maximum ,so option c is correct.
During isovolumetric relaxation, AV and semilunar valve opens and the ventricular pressure decrease.
The human heart's activity from the start of one heartbeat to the start of the next is known as the cardiac cycle. It consists of twophases: a diastole, in which the heart muscle relaxes and re-fills with blood, and a systole, in which the heart muscle contracts forcefully and pumps blood. The heart quickly relaxes and expands after emptying to receive a second inflow of blood returning from the lungs and other body systems, then contracts to send blood back to those systems. A healthy heart must fully expand before it can once again pump effectively.
Isovolumetric relaxation is the second heart sound is produced when the aortic and pulmonary valves close when the ventricular pressures fall below the diastolic aortic and pulmonary pressures (80 mmHg and 10 mmHg, respectively) . The start of diastole is indicated by this.
So, Ventricular contraction and Isovolumetric relaxation gets distinguished by their specific characteristics.
