Among the following animals, choose the one having three pairs of legs.

The classification of arthropods is primarily based on their body segments and leg counts. Arachnids, which include spiders, scorpions, and mites, are characterized by having two body parts and four pairs of legs, totaling eight legs [1]. While mites may hatch with six legs in their larval stage, they develop eight legs as adults. In contrast, insects are defined by having three body segments (head, thorax, and abdomen) and exactly three pairs of legs, totaling six legs [1]. A 'bug' is scientifically classified as an insect within the order Hemiptera. Since bugs are true insects, they possess the characteristic three pairs of legs attached to the thorax. Therefore, among the given options, only the bug fits the description of having three pairs of legs, while the others are arachnids with four pairs.

Sources

1. [1] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 9: Indian Biodiversity Diverse Landscape > Arachnids > p. 156