This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition & Digestion, Subject name: Biochemistry
[{'content': 'Site of absorption of Vitamin B12: \nSelect and explain. \nA. Ileum, B. Jejunum, C. Duodenum, D. Stomach', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. A. Ileum(Ref: Harper 31/e page 533-540)Site of absorption of Iron--Proximal DuodenumSite of absorption of Folic acid--Proximal jejunumSite of absorption of Cobalamin--Ileum', 'role': 'assistant'}]