What term refers to the nervous system of insects?

The term that refers to the nervous system of insects is "ventral." In insects, the ventral nerve cord is a critical component of their nervous system. It runs along the belly (ventral side) of the insect and is responsible for relaying signals between the brain and the rest of the body. The structure of the insect nervous system is quite different from that of vertebrates; insects have a more centralized nerve cord that is integral to their movement and behavior.

The other options do not pertain to the nervous system of insects. "Pretarus" is not a recognized term within entomology or insect anatomy. "Coxa" refers to a specific joint or part of an insect's leg, particularly the hip joint where the leg meets the body. "Hexapoda" is the scientific subphylum to which insects belong, characterized by having six legs but does not refer to the nervous system directly. Understanding these terms helps clarify the anatomical and functional characteristics of insects.