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: Medicine
The most common hormone other than gastrin, contained in the gastrin-secreting islet cell tumor is - 
Select and explain. 
A. ACTH, B. Glucagon, C. Melanocyte stimulating hormone, D. Growth hormone releasing factor
A: ACTH
Answer: A: ACTH 
Explanation: None