This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Local and Regional Anesthesia), Subject name: Anaesthesia
[{'content': 'Longest acting local anaesthetic drug is? \nSelect and explain. \nA. Procaine, B. Prilocaine, C. Lignocaine, D. Bupivacaine', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. (d) BupivacaineRef: Morgan's Anaesthesiology 4/e, p 269", 'role': 'assistant'}]