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': 'Bone marrow depression is seen with. \nSelect and explain. \nA. Halothene, B. N20, C. Ether, D. Isoflurane', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. N2O', 'role': 'assistant'}]