Which insects typically undergo gradual metamorphosis?

Insects that undergo gradual metamorphosis, also known as hemimetabolism, transition through three life stages: egg, nymph, and adult. The nymphs resemble miniature adults and undergo several molts to reach maturity, without a distinct pupal stage. Grasshoppers and bed bugs are prime examples of insects that exhibit this type of development.

Grasshoppers develop through a series of nymph stages, where they gradually increase in size and complexity, eventually emerging as fully developed adults. Similarly, bed bugs go through immature stages that closely resemble the adult form, except they are smaller and lack wings.

This contrasts with insects like flies, mosquitoes, butterflies, and moths, which undergo complete metamorphosis (holometabolism), characterized by distinct larval and pupal stages that do not resemble the adult form. Bees and wasps also exhibit complete metamorphosis, beginning life as eggs and progressing through larval and pupal stages before emerging as adults. Thus, the correct answer focuses on the insects that follow the gradual progression typical of hemimetabolic insects.