This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
Isovolumetric relaxation is defined as 
Select and explain. 
A. Relaxation of both atria, B. Relaxation of both atria with all valves open, C. Relaxation of LV with mitral & aortic valve closed, D. All of the above
C: Relaxation of LV with mitral & aortic valve closed
Answer: C: Relaxation of LV with mitral & aortic valve closed 
Explanation: ‘Isovolumetric’ means the volume remains same. That occurs only when both the valves are closed.