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
Iron is most commonly absorbed from 
Select and explain. 
A. Duodenum and upper jejunum, B. Lower jejunum, C. Stomach, D. Ileum
A: Duodenum and upper jejunum
Answer: A: Duodenum and upper jejunum 
Explanation: 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