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
Of the following which one correlates with isovolumic contraction phase: 
Select and explain. 
A. AV opening and aoic and pulmonary valve closure, B. AV closure and aoic & pulmonary valve opening., C. Both valves are closed, D. Both valves are open
C: Both valves are closed
Answer: C: Both valves are closed 
Explanation: C i.e. Both value are closed