This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vitamins and Minerals, Subject name: Biochemistry
[{'content': 'No of iron in ferritin: \nSelect and explain. \nA. 4, B. 40, C. 400, D. 4000', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D. 4000FerritinStorage Form of IronPoly nuclear complex of Hydrous ferric oxide carry about 4500 iron atomsSeen in Intestinal cells, Liver, Spleen Bone marrow Sensitive index of Body iron stores', 'role': 'assistant'}]