All of the following can cause obstruction of hepatobiliary system EXCEPT: (A) Ankylostoma duodenale, (B) Ascaris lumbricoides, (C) Clonorchis sinensis, (D) Fasciola hepatica
Answer is B. Ankylostoma * The adult parasites live in the small intestine of man, mostly in the jejunum, less frequently in duodenum and infrequently in the ileum. * Ascaris and liver flukes are known to cause biliary obstruction.