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': 'The first anaesthetic used in clinical anaesthesia: \nSelect and explain. \nA. Bupivacaine, B. Cocaine, C. Lidocaine, D. Procaine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Cocaine', 'role': 'assistant'}]