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: Medicine
The murmur of hypertropic obstructive cardio myopathy is decreased in which of the following- 
Select and explain. 
A. Supine position, B. Standing position, C. Valsalva maneuver, D. Amyl nitrate inhalation
A: Supine position
Answer: A: Supine position 
Explanation: None