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
Most common organic cause of erectile dysfunction 
Select and explain. 
A. Atherosclerosis, B. Multiple sclerosis, C. Penile fibrosis, D. Peyronie's disease
A: Atherosclerosis
Answer: A: Atherosclerosis 
Explanation: M/c organic cause of ED is Atherosclerosis.