This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Mycobacterial Infections, Subject name: Dental
[{'content': 'The most potent anti-leprotic drug is? \nSelect and explain. \nA. Rifampicin, B. Dapsone, C. Clofazimine, D. Sulfasalazine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Rifampicin is bactericidal for M. leprae in very low dosage and acts much more rapidly than Dapsone, rendering the patient non-contagious in a few days or weeks. It acts by inhibiting DNA dependent RNA polymerase.', 'role': 'assistant'}]