An immigrant from the Far East develops malaise, fever, and rigors, followed by upper right quadrant abdominal pain, vomiting, jaundice, and itching. His urine is dark and his feces are pale. Infestation with which of the following parasites is most strongly suggested by this patient's presentation?

The patient is suffering from suppurative (bacterial) cholangitis, which can occur as a complication of infestation by the roundworm, Ascaris lumbricoides and by the liver flukes, Clonorchis sinensis and Fasciola hepatica. Biliary tract obstruction produces jaundice and extreme itching, with dark urine and pale feces. Therapy typically includes emergency endoscopic sphincterotomy to improve biliary drainage, antibiotics, and anthelmintic agents. Enterobius vermicularis causes pinworm infections. Plasmodium ovale causes malaria. Taenia solium is the pork tapeworm. Adult tapeworms cause taeniasis, while the larvae are responsible for cysticercosis. Ref: Ray C.G., Ryan K.J. (2010). Chapter 56. Trematodes. In C.G. Ray, K.J. Ryan (Eds), Sherris Medical Microbiology, 5e.