This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: GIT and hepatobiliary system, Subject name: Radiology
You are shown two films from an ERCP in a 40-year-old woman with abdominal pain. What is the MOST likely diagnosis? 
Select and explain. 
A. Ductal adenocarcinoma, B. Double-duct sign, C. Pancreas divisum, D. Annular pancreas
C: Pancreas divisum
Answer: C: Pancreas divisum 
Explanation: A. A double duct sign (dilation of both the common bile duct and main pancreatic duct) is not seen. B. The common bile duct is not dilated. C. The first image shows injection of the major papilla and opacification of the common bile duct and duct of Wirsung, but no opacification of the main pancreatic duct. The second image shows injection of the minor papilla with opacification of the main pancreatic duct, but no opacification of the common bile duct. This is characteristic of pancreas divisum. D. No opacified pancreatic duct is seen to the right of the duodenum.