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: Microbiology
True about methicillin-resistant Staphylococcus aureus (MRSA) is 
Select and explain. 
A. Isoxazolyl penicillin is highly effective, B. All MRSA are multidrug resistance, C. Vancomycin is effective, D. MRSA are more virulent than sensitive strains
B: All MRSA are multidrug resistance
Answer: B: All MRSA are multidrug resistance 
Explanation: Penicillin resistance may also be due to alterations in penicillin-binding protein PBP2a and changes in bacterial surface receptors, reducing binding of beta-lactam antibiotics to cells. This resistance also extend to cover beta lactamase resistant penicillin such as methicillin and cloxacillin(MRSA)
Some of these strains may show resistance to other antibiotics like erythromycin, tetracyclines, aminoglycosides and heavy metals.