This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti Microbial, Subject name: Pharmacology
[{'content': 'MRSA is resistant to: \nSelect and explain. \nA. Vancomycin, B. b lactams, C. Linezolid, D. Meropenems', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ref: Sharma & Sharma 3nl ed. P 733* No b Lactams are effective against MRSA, EXCEPT 5th generation cephalosporins like Ceftaroline and Ceftibiprole.* DOC for MRSA: Vancomycin* DOC for VRSA: Daptomycin* Drugs used in VRSA: Quinpristin, Daptomycin, Linezolid', 'role': 'assistant'}]