Which of the following does NOT belong to Class Arachnida?

Class Arachnida includes organisms characterized by having eight legs and two main body segments, the cephalothorax and abdomen. This classification encompasses a variety of creatures such as ticks, spiders, and scorpions, which all share these defining physical traits.

Caterpillars, on the other hand, belong to a different class entirely—Insecta. These larvae of moths and butterflies typically have three pairs of legs, along with several additional prolegs, and they undergo a complete metamorphosis, transforming into adults with different structures and characteristics. This fundamental difference in body structure and classification clearly distinguishes caterpillars from members of Class Arachnida, making them the correct choice for an organism that does not belong to this class.