Which group of insects undergoes complete metamorphosis?

Complete metamorphosis is a developmental process that involves four distinct life stages: egg, larva, pupa, and adult. This life cycle is characteristic of certain groups of insects, specifically those belonging to the order Lepidoptera (which includes butterflies and moths) and the order Coleoptera (beetles). These insects begin their life as eggs, hatch into larval forms (caterpillars for butterflies, grubs for beetles), enter a pupal stage where they undergo transformation, and finally emerge as mature adults.

Choosing butterflies and beetles highlights the two prominent examples of insects that exemplify this biological process, making the answer accurate. Other options describe general characteristics or categories of insects that do not specifically indicate complete metamorphosis. Egg-laying insects can include both those that undergo complete and incomplete metamorphosis. Winged insects may belong to various categories, not all of which undergo complete metamorphosis. Stinging insects can refer to wasps or bees, which typically undergo incomplete metamorphosis with only three life stages: egg, nymph, and adult. Thus, the identification of butterflies and beetles distinctly represents the complete metamorphosis process.