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: Psychiatry
[{'content': 'Most accurate treatment of erectile dysfunction - \nSelect and explain. \nA. Sildenafil, B. Master and Johnson technique, C. Beta blockers, D. Papaverine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Sildenafil is the DOC for erectile dysfunction.', 'role': 'assistant'}]