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: Pharmacology
[{'content': 'Active metabolite of carisoprodol is: \nSelect and explain. \nA. Amphetamine, B. Meprobamate, C. Doxylamine, D. Dimethadione', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Meprobamate', 'role': 'assistant'}]