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': 'Which of the following antibacterial causes both ototoxicity and nephrotoxicity : \nSelect and explain. \nA. Methicillin, B. Vancomycin, C. Clindamycin, D. Azithromycin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]