Which of the following are thought to be most closely related to humans?

ants

sea stars

earthworms

snails

jellies

Sea Stars, because they are also deuterostomes.

Star fishes are more related to humans than other species given in the option.

Explanation: The star fishes have five arms while humans also have arms but only two which is a dissimilar. The body of the star fish are covered with spike while humans are covered with hair (facial/body) which is a dissimilar. The skeleton of the star fish is covered with outer cover which is similar to humans. The digestive systems of the star fish and human are not very different from each other. The star fish performs digestion with less organs compared to humans. The nervous system, circulatory system, and digestive system different for both species.

But from the given options, star sea is mostly related to humans.