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': 'Respiratory depression is seen with \nSelect and explain. \nA. Tranquilizers, B. Non-barbiturates, C. Synthetic narcotics, D. Antidepressants', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]