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: Surgery
[{'content': 'Which of the anaesthetic agent is maximally metabolized: \nSelect and explain. \nA. Methoxyflurane, B. Halothane, C. Nitrous oxide, D. Isoflurane', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Methoxyflurane is most extensively metabolized. (50%), to liberate very high fluoride.', 'role': 'assistant'}]