This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Inhalational Anesthetic Agents, Subject name: Anaesthesia
[{'content': 'Which anaesthetic agent can have teratogenic effect? \nSelect and explain. \nA. N2O, B. Halothane, C. Isoflurane, D. Desflurane', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Nitrous oxide can have teratogenic effect if used for prolonged period of time.', 'role': 'assistant'}]