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: Social & Preventive Medicine
[{'content': 'What is the recommended drug for treatment of carriers of diphtheria? \nSelect and explain. \nA. Oral penicillin, B. Injectable penicillin, C. Azithromycin, D. Erythromycin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Carriers of diphtheria should be treated with a 10 days course of erythromycin. Ref: Park 21st edition, page 151.', 'role': 'assistant'}]