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: Physiology
[{'content': 'Which of the following metabolizes arginine? \nSelect and explain. \nA. Mycoplasma pneumoniae, B. Mycoplasma genitalium, C. Mycoplasma hominis, D. Ureaplasma urealyticum', 'role': 'user'}, {'content': 'Answer: C \nExplanation: M. hominis metabolizes arginine, with the production of potentially cytotoxic amounts of ammonia. Ureaplasmas have been placed in a separate genus because of their unique urease activity; the metabolism of urea also produces ammonia.', 'role': 'assistant'}]