Which of the following orders includes mosquitoes?

Mosquitoes belong to the order Diptera, which is characterized by insects that typically have a single pair of wings and undergo complete metamorphosis. This order is quite diverse, including not only mosquitoes but also flies and gnats. The defining feature of Diptera is the presence of halteres, which are evolutionary modified wings that help with balance and flight stability.

In contrast, the other orders mentioned have distinct characteristics that do not include mosquitoes. For example, Siphonaptera refers to fleas, Isoptera includes termites, and Coleoptera is the order for beetles. Each of these groups has unique anatomical and behavioral traits that clearly separate them from mosquitoes. Thus, understanding these classifications helps clarify why mosquitoes are correctly classified under the order Diptera.