What stages are characteristic of no metamorphosis?

The characteristic stages of no metamorphosis, or ametabolous development, involve the progression from an egg to a young form and then to the adult stage. In this context, the young form resembles a smaller version of the adult and undergoes growth without undergoing any drastic changes in body structure or form, which distinguishes this development process from those that involve metamorphosis.

In contrast, options that include larvae or nymphs suggest that there are intermediate life stages that undergo significant transformation before reaching adulthood. For example, larval stages are common in complete metamorphosis, while nymphs indicate an incomplete metamorphosis where the young gradually resembles the adult but still goes through distinct changes. The inclusion of pupa or naiad stages further implies that there are transitional life stages involved, which are not present in ametabolous development. Thus, the progression from egg to young to adult is the defining characteristic of no metamorphosis.