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': 'A boy is having diarrhea, rhinorrhoea, sweating & lacrimation. What is the most probable diagnosis: \nSelect and explain. \nA. Cocaine withdrawal, B. Heroin withdrawal, C. Alcohol withdrawal, D. LSD withdrawal', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Heroin withdrawal', 'role': 'assistant'}]