Which of the following describes insects?

Insects are classified as arthropods, which are characterized by their segmented bodies and jointed appendages. Specifically, insects have a body that is divided into three main segments: the head, thorax, and abdomen. In addition to this segmented body structure, insects possess three pairs of legs, resulting in a total of six legs. This distinct anatomy differentiates them from other arthropods and allows for a wide range of movement and adaptability in various environments.

The other options describe different types of organisms. The first option refers to creatures with a body structure typical of arachnids (such as spiders), which have eight legs and two body segments, not three. The third option describes warm-blooded vertebrates, such as mammals and birds, which are entirely separate from insects in classification. The last option mistakenly identifies spores, which are a reproductive structure of plants and fungi, not a characteristic of any animal group, including insects. Thus, the description that best fits insects is the one stating that they are arthropods with a body composed of three segments and three pairs of legs.