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: Pharmacology
[{'content': 'Rate of iron uptake is regulated by which one of the following : \nSelect and explain. \nA. Mucosal cell iron stores, B. Route of administration, C. Preparation administered, D. Age of the patient', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]