This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
most effective bactericidal among the following ? 
Select and explain. 
A. NADPH OXIDASE, B. FREE RADICLES, C. MYELOPEROXIDASES-HALIDE SYSTEM, D. ACID HYDROLASE
A: NADPH OXIDASE
Answer: A: NADPH OXIDASE 
Explanation: MOST EFFECTIVE BACTEROCIDAL : 1st is NADPH OXIDASE 2nd mpo- halide system - its not antioxidants while others are both antioxidants and antimicrobials others like free radicles and h2o2 also paicipate in killing and degradation . ref : robbins 10th ed