This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Disorders of Gallbladder and Extrahepatic Biliary Tract, Subject name: Pathology
[{'content': 'The complications of gallstones include all of the following except: \nSelect and explain. \nA. Adenocarcinoma of ampulla of Vater, B. Acute intrahepatic cholangitis, C. Acute pancreatitis, D. Gangrenous cholecystitis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans (a) Adenocarcinoma of ampulla of VaterThe complications of gallstones include gangrenous cholecystitis by pressure on the mucosa and blood vessels in an acutely inflamed gallbladder* Cholangitis by blocking the major biliary ducts and allowing bacteria to ascend into the liver* Obstructive jaundice by blocking the common duct* Acute pancreatitis by blocking the ampulla of Vater or a major pancreatic duct* Gallstone ileus.', 'role': 'assistant'}]