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: Biochemistry
[{'content': 'Ammonia is detoxified in brain to- \nSelect and explain. \nA. Uric acid, B. GABA, C. Urea, D. Glutamine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The brain is a rich source of glutamine synthase and predominantly detoxifies ammonia by synthesis of glutamate.', 'role': 'assistant'}]