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
Mechanism of action of penicillins and cephalosporins is to inhibit : 
Select and explain. 
A. Cell wall synthesis, B. Leakage from cell membrane, C. Protein synthesis, D. DNA gyrase
A: Cell wall synthesis
Answer: A: Cell wall synthesis 
Explanation: None