This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition and health, Subject name: Social & Preventive Medicine
[{'content': 'Iron absorption from intestine is regulated by - \nSelect and explain. \nA. Acid secretion in stomach, B. Reducing substances in food, C. Mucosal block in the intestinal cells in according to iron requirement, D. Alkaline medium in small intestine', 'role': 'user'}, {'content': "Answer: C \nExplanation: The iron absorption is based on Mucosal block in the intestinal cells in according to iron requirement. REF. PARK'S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICAL 21ST EDITION. PAGE NO - 623", 'role': 'assistant'}]