This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gall Bladder & Bile Ducts, Subject name: Surgery
[{'content': 'Mirizzi syndrome is: \nSelect and explain. \nA. GB stone compressing common hepatic duct, B. GB carcinoma invading IVC, C. GB stone causing cholecystitis, D. Pancreatic carcinoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) GB stone compressing common hepatic ductCSENDES CLASSIFICATION of Mirizzi Syndrome -5 types.* Type 1: Only compression of Common Duct.* Type 2: Erosion less than 1/3rd* Type 3: Erosion more than 1/3rd* Type 4: Total destruction* Type 5: Associated Cholecysto Enteric Fistula', 'role': 'assistant'}]