Of the following, which is a characteristic of arachnids?

Arachnids are characterized by having two body regions, which are the cephalothorax (a fusion of the head and thorax) and the abdomen. This anatomical structure differentiates them from insects, which have three separate body sections: head, thorax, and abdomen. Additionally, arachnids typically have eight legs, unlike insects that possess three pairs of legs.

The presence of wings and antennae, as mentioned in another option, is a feature associated with insects and does not apply to arachnids. Similarly, arachnids do not have two pairs of legs; they possess four pairs. This understanding of arachnid anatomy is crucial for identification and classification within entomology and integrated pest management.