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: Anaesthesia
[{'content': 'Anaesthetic agent of choice in renal failure – \nSelect and explain. \nA. Methoxyflurane, B. Isoflurane, C. Enflurane, D. None', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Amongst the given options isoflurane is best.\nOverall, Desflurane is best in renal failure.', 'role': 'assistant'}]