This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
[{'content': 'Source of ammonia in urine \nSelect and explain. \nA. Glutaminase, B. Urease, C. Glutamate dehydrogenase, D. Arginase', 'role': 'user'}, {'content': 'Answer: A \nExplanation: .', 'role': 'assistant'}]