Ascaris lumbricoides is found living in the intestine of

The correct option is Homo sapiens.

Ascaris lumbricoides is a large roundworm belonging to the phylum Nematoda. It is a well-known obligate endoparasite of humans (Homo sapiens) and is the causative agent of the disease known as ascariasis.
The adult worms inhabit the lumen of the human small intestine, where they survive by feeding on the semi-digested food passing through the host's digestive tract.

While a closely related species, Ascaris suum, is found in pigs, Ascaris lumbricoides is specifically adapted to complete its life cycle and reproduce within human hosts.