What arachnid feature distinguishes them from insects?

Arachnids are distinguished from insects primarily by their body structure, which consists of two main segments: the cephalothorax and the abdomen. This bipartite division is a key anatomical feature that sets arachnids apart from insects, which have three body segments: the head, thorax, and abdomen.

The other options highlight features not associated with arachnids. For instance, arachnids do not have wings; thus, the presence of wings for flying is a characteristic attributed to some insect species. Additionally, arachnids have eight legs, not six pairs, which further delineates them from insects. Lastly, arachnids do not have antennae; they possess specialized mouthparts and other structures. Understanding these distinctions reinforces the classification and biological differences between these two groups of arthropods.