Which order does the book louse belong to?

The book louse is categorized under the order Insecta, which encompasses all insects. This classification includes a wide variety of species characterized by a segmented body, exoskeleton, and jointed appendages. Book lice are small, wingless insects that typically feed on mold and book bindings, especially in damp environments. Their prevalence in households often draws attention, but they do not pose a significant threat to human health or property.

The other options represent different insect orders. Collembola refers to springtails, known for their ability to jump, while Neuroptera includes insects like lacewings, which possess net-like wings. Orthoptera encompasses grasshoppers, crickets, and similar insects, which have different anatomical and behavioral traits. Thus, the classification of book lice under the order Insecta correctly reflects their biological characteristics and relationship to the broader category of insects.