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
Cholangiocarcinoma has been associated with infection by: 
Select and explain. 
A. Paragonimus westermani, B. Clonorchis sinensis, C. Loa Loa, D. Schistosoma haematobium
B: Clonorchis sinensis
Answer: B: Clonorchis sinensis 
Explanation: 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.