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': 'Which of the following is not an anesthetic that acts for more than 2hrs? \nSelect and explain. \nA. Bupivacaine, B. Prilocaine, C. Etidocaine, D. Tetracaine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Prilocaine have only intermediate duration and potency (30-90 min). Tetracaine, Bupivacaine, Etidocaine have long duration and potency (>120 min). Ref: Miller Anaesthesia, 5th Edition, Page 586.', 'role': 'assistant'}]