This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Physiology
Motilin is secreted by cells in 
Select and explain. 
A. Stomach, B. Duodenum/ileum, C. Pancreas, D. Liver
B: Duodenum/ileum
Answer: B: Duodenum/ileum 
Explanation: Motilin is a hormone released from endocrine cells within the epithelium of small intestine. Ref: Guyton,11e