This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Enzyme that protects the brain from free radical injury is 
Select and explain. 
A. Myeloperoxidase, B. Superoxide dismutase, C. MAO, D. Hydroxylase
B: Superoxide dismutase
Answer: B: Superoxide dismutase 
Explanation: Superoxide dismutase ref Robbins 7/e p17 , Harrison 17/e p 2572 ,9/e p48.