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: Pharmacology
[{'content': 'Dose of all is reduced in renal failure, except ? \nSelect and explain. \nA. INH, B. Rifabutin, C. Ethambutol, D. Kanamycin', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Rifabutin", 'role': 'assistant'}]