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What is Cholangiocarcinoma is caused by -a) Fasciola infestationb) Clonorchis infestationc) Paragonimus infestationd) Ascaris infestatione) None of these and explain in detail?
Parasites

Schistosoma haematobium
Clonorchis sinensis
Opisthorchis viverrini

Malignancy

Squamous cell carcinoma of urinary bladder
Cholangiocarcinoma of liver, bile duct and Adenocarcinoma of pancreas
Cholangiocarcinoma of bile duct