This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
[{'content': 'The byproduct of GABA is \nSelect and explain. \nA. Glutamate, B. Aspaate, C. Glycine, D. Succinate', 'role': 'user'}, {'content': 'Answer: D \nExplanation: It is clear from this picture that GABA metabolite is succinate.', 'role': 'assistant'}]