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': 'Pin code index of nitrous oxide is: March 2013 (c) \nSelect and explain. \nA. 1, 6, B. 2, 5, C. 2, 6, D. 3, 5', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D i.e. 3, 5', 'role': 'assistant'}]