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': 'Amoxicillin + clavulanic acid is active against the following organisms EXCEPT : \nSelect and explain. \nA. Methicillin resistant Staph. aureus, B. Penicillinase producing Staph. aureus, C. Penicillinase producing N. gonorrhoeae, D. β-lactamase producing E. coli', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Staphylococcus aureus develops resistance to methicillin by acquiring altered penicillin-binding proteins that have low affinity. No Beta-lactam antibiotic is effective against MRSA.\nClavulanic acid is an inhibitor of β-lactamase. It can restore the sensitivity of penicillins against the organisms who have developed penicillinases.', 'role': 'assistant'}]