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': 'Which of the following drugs is currently widely used in treating opioid-dependent individuals? \nSelect and explain. \nA. Codeine, B. Methadone, C. Alphaprodine, D. Pentazocine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]