Ascariasis is characterised by:

The correct option is B Infection of the small intestine
Ascariasis is an infection of the small intestine caused by the parasite, Ascaris lumbricoides. Ascariasis infection usually causes no symptoms, but heavier infestation can lead to problems in the lungs or intestines. The multiplication of Ascaris worms results in symptoms like internal bleeding, muscular pain, fever, anaemia and blockage of the intestinal passage.