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': 'The drug for OPD analgesia is - \nSelect and explain. \nA. Morphine, B. Pethidine, C. Fentanyl, D. Alfentanil', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e., Alfentanil Drugs useful for day care surgery o Propofol o Sevoflurane, desflurane & isoflurane o Midazolam o Mivacurium o Alfantanil", 'role': 'assistant'}]