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: Biochemistry
Free radical scavenzer is 
Select and explain. 
A. Peroxidase, B. Catalase, C. Dehydrogenase, D. All of the above
B: Catalase
Answer: B: Catalase 
Explanation: Ans. is 'b' i.e., Catalase Antioxidant enzymes are catalase, superoxide desmutase and glutathione peroxidase.These enzyme together act as free radical scavenzing system.