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: Biochemistry
[{'content': 'Plasma levels of which of the following are likely to be lower than normal in a case of severe liver disease? \nSelect and explain. \nA. NH3, B. NH4+, C. Urea, D. Alanine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: .', 'role': 'assistant'}]