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: Ophthalmology
Which does not handle free radicals inside lens – 
Select and explain. 
A. Vitamin A, B. Vitamin C, C. Vitamin E, D. Catalase
A: Vitamin A
Answer: A: Vitamin A 
Explanation: Enzymatic antioxidant mechanisms :- Reduced glutathione (most important), glutathione peroxidase, superoxide dismutase, catalase.
Non-enzymatic defence mechanisms :- Vitamin C, Vitamin E, and possibly carotenoids.
Some textbooks have also mentioned vitamin A as an anti-oxidant in lens. But, the best answer here is vitamin A because all other options have been mentioned as anti-oxidants in all textbooks, while vitamin A has been mentioned only in some textbooks.