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
[{'content': "Most common organic cause of erectile dysfunction \nSelect and explain. \nA. Atherosclerosis, B. Multiple sclerosis, C. Penile fibrosis, D. Peyronie's disease", 'role': 'user'}, {'content': 'Answer: A \nExplanation: M/c organic cause of ED is Atherosclerosis.', 'role': 'assistant'}]