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: Physiology
[{'content': 'GABA is produced from: \nSelect and explain. \nA. Alanine, B. Glycine, C. Glutamate, D. Glutamine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Glutamate', 'role': 'assistant'}]