This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Pharmacology
[{'content': 'Iron is most commonly absorbed from \nSelect and explain. \nA. Duodenum and upper jejunum, B. Lower jejunum, C. Stomach, D. Ileum', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Refer Katzung 11/e p 571 Maximum iron absorption occurs in duodenum and proximal jejunum Vitamin B12 is absorbed in distal ileum whereas folic acid is absorbed in proximal jejunum', 'role': 'assistant'}]