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: Medicine
[{'content': 'Worldwide accepted minimum dose of penicillin in latent syphilis- \nSelect and explain. \nA. 4.8 mega units, B. 6.0 mega units, C. 7.0 mega units, D. 10 units', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]