This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anaesthesia, Subject name: Pharmacology
[{'content': 'The local anaesthetic with the longest duration of action is : \nSelect and explain. \nA. Procaine, B. Chlorprocaine, C. Lignocaine, D. Dibucaine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: * Longest acting, most potent and most toxic LA is dibucaine. * Chlorprocaine is the shoest acting LA.', 'role': 'assistant'}]