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: Physiology
Intrinsic factor is required for absorption of ? 
Select and explain. 
A. Folic acid, B. Vitamin B12, C. Vitamin B, D. Vitamin B2
B: Vitamin B12
Answer: B: Vitamin B12 
Explanation: Ans. is 'b' i.e., Vitamin B12