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
Lipid soluble plasma membrane associated antioxidant? 
Select and explain. 
A. Ubiquitin, B. Vitamin E, C. Vitamin C, D. Glutathione
B: Vitamin E
Answer: B: Vitamin E 
Explanation: Ans. is 'b' i.e., Vitamin E"Alpha-tocopherol is the only lipid soluble, chainbreaking antioxidant present in biological membranes".