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
All of the following statements about penicillin-binding proteins are true EXCEPT : 
Select and explain. 
A. Present on cell surface, B. Mutation in PBPs gives rise to resistance, C. These are target site of vancomycin, D. These are targeted by imipenem
C: These are target site of vancomycin
Answer: C: These are target site of vancomycin 
Explanation: Beta-lactam antibiotics act by inhibiting the cross-linking of peptidoglycan chains in the bacterial cell wall. This action is carried out by transpeptidase enzyme. Transpeptidases and similar enzymes involved in cross-linking are called penicillin-binding proteins (PBPs). All beta-lactam antibiotics bind to PBPs and inhibit cell wall synthesis. 
The drugs in p-lactam category are:

Penicillin
Cephalosporins
Carbapenems e.g imipenem
Monobactam e.g. aztreonam
Mutation in PBPs is an important cause of methicillin resistance in Staphylococcus aureus.
Vancomycin does not bind to PBPs but acts by inhibiting transglycosylase.