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: Pharmacology
[{'content': 'All of the following are intravenous anesthetic induction agents except : \nSelect and explain. \nA. Thiopentone sodium, B. Ketamine, C. Etomidate, D. Bupivacaine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]