This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bile duct, Subject name: Surgery
[{'content': 'Cholangiocarcinoma has been associated with infection by: \nSelect and explain. \nA. Paragonimus westermani, B. Clonorchis sinensis, C. Loa Loa, D. Schistosoma haematobium', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Risk Factors for Cholangiocarcinoma Choledocholithiasis Clonorchis sinensis and Opisthorchis viverrini Cirrhosis Radon Asbestos, Nitrosamines, Dioxin (AND) Diabetes, Obesity, OCPs, Smoking, Thorotrast, Isoniazid (DOSTI) Most common symptom is jaundice IOC - MRI + MRCP Rx Hilar cholangiocarcinoma - CBD Resection + routine caudate lobectomy + Lymphadenectomy Distal cholangiocarcinoma - Pylorus preserving whipples procedure Gemcitabine + cisplatin is used for advanced cases.', 'role': 'assistant'}]