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: Microbiology
[{'content': 'All of the following are known to cause biliary obstruction EXCEPT: March 2013 \nSelect and explain. \nA. Clonorchis, B. Ascariasis, C. Ancylostoma, D. Fasciola', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C i.e. Ancylostoma Site of locution of Ancylostoma is small intestine', 'role': 'assistant'}]