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': 'Methicillin-resistant staphylococci do not respond to β-lactam antibiotics because: \nSelect and explain. \nA. They produce a b-lactamase which destroys methicillin and related drugs., B. They elaborate an amidase which destroys methicillin and related drugs., C. They are less permeable to b-lactam antibiotics., D. None of the above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Resistance to most penicillins is due to elaboration of beta-lactamase.\xa0\n\nMethicillin is most resistant penicillin to β-lactamase.\xa0\nStaphylococcus aureus develops resistance to methicillins by acquisition of altered penicillin binding proteins.', 'role': 'assistant'}]