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
Iron absorption is increased by the following factor in diet: 
Select and explain. 
A. Vitamin-C, B. Phytic acid, C. Fibre diet, D. Phosphates
A: Vitamin-C
Answer: A: Vitamin-C 
Explanation: In a vegetarian diet, nonheme iron is absorbed very poorly because of the inhibitory action of a variety of dietary components, paicularly phosphates, phytates and high fibre content. Ascorbic acid and meat facilitate the absorption of nonheme iron. Ascorbate forms complexes with and/or reduces ferric to ferrous iron. Meat facilitates the absorption of iron by stimulating production of gastric acid; other effects also may be involved. Either of these substances can increase availability several fold. Ref: Kaushansky K., Kipps T.J. (2011). Chapter 37. Hematopoietic Agents: Growth Factors, Minerals, and Vitamins. In B.C. Knollmann (Ed), Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e.