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: Pathology
[{'content': 'Sclerosis of bile duct is seen in ? \nSelect and explain. \nA. Primary sclerosing cholangitis, B. Obstructive jaundice, C. Bile duct atresia, D. Bile stones', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Primary sclerosing cholangitis", 'role': 'assistant'}]