Which stages are involved in complete metamorphosis?

Complete metamorphosis, also known as holometabolism, consists of four distinct stages: egg, larvae, pupa, and adult. This process starts with the egg stage, where fertilization occurs, and the embryo develops. Once the egg hatches, it enters the larval stage, during which the organism grows and feeds actively, typically undergoing several molts.

After the larval stage, the organism enters the pupal stage, a transformative phase during which it undergoes significant physiological changes. This stage is often spent in a protective casing, allowing the organism to rearrange its body structure in preparation for emerging as an adult.

Finally, the adult stage is achieved, characterized by the mature form of the insect, capable of reproduction. This clear division into these four stages sets complete metamorphosis apart from incomplete metamorphosis, where nymphs resemble smaller versions of adults and do not have a distinct pupal stage. The inclusion of larvae, pupa, and adult in the correct answer highlights the complexity and diversity of developmental processes in insects undergoing complete metamorphosis.