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': 'At the end of anaesthesia after discontinuation of nitrous oxide and removal of endotracheal tube, 100% oxygen is administered to the patient to prevent – \nSelect and explain. \nA. Diffusion Hypoxia, B. Second gas effect, C. Hyperoxia, D. Bronchospasm', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Diffusion hypoxia can be prevented by continuing 100% O2 inhalation for a few minutes after discontinuing N2O,\xa0instead of straight away switching over to air.', 'role': 'assistant'}]