This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vitamins, Subject name: Biochemistry
Major function of Vitamin E in the body - 
Select and explain. 
A. Regulation of energy metabolism, B. Carboxvlation reaction, C. Blood clotting, D. Protection of biological membrane from free radical damage
D: Protection of biological membrane from free radical damage
Answer: D: Protection of biological membrane from free radical damage 
Explanation: Ans. is 'd'i.e., Protection of biological membrane from free radical damage o The most important function of vitamin E in human beings is to act as an anti-oxidant.o It prevents the oxidation of other antioxidants, e.g, carotenes, vitamin A and vitamin C.o Vitamin E is the lipid-soluble antixodant in cell membranes and plasma lipoproteins.o The main function of vitamin E is as a chain-breaking, free radical-trapping antioxidant in cell membranes and plasma lipoproteins by reacting with lipid peroxide radicals formed by peroxidation of polyunsatured fatty acid,o Vitamin E prevents rancidity of fats due to its antioxidant action.