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': 'In patients of substance-abuse, drugs used are: \nSelect and explain. \nA. Naltrexone, B. Naloxone, C. Clonidine, D. All', 'role': 'user'}, {'content': 'Answer: D \nExplanation: A i.e. Naltrexone; B i.e. Naloxone; C i.e. Clonidine', 'role': 'assistant'}]