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': 'Which of the following local anesthetic should be avoided in spinal anesthesia? \nSelect and explain. \nA. Mepivacaine, B. Prilocaine, C. Bupivacaine, D. Chlorprocaine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Chlorprocaine is avoided in spinal anesthesia as it can cause spinal paraplegia because of a neurotoxic compound sodium metabisulphite, which is used as a preservative.', 'role': 'assistant'}]