Blow fly life cycle consists of which four developmental stages?

• A. Egg, larva, pupa, and adult.
• B. Egg, chrysalis, nymph, adult.
• C. Egg, pupa, larva, adult.
• D. Egg, larva, pupa, nymph.

Answer: (A)

Blow flies undergo complete metamorphosis, meaning there are four distinct life stages in a fixed sequence: egg, larva, pupa, and adult. The female lays eggs that hatch into maggot-like larvae; the larvae then enter a pupal stage where transformation occurs; finally, an adult fly emerges. This sequence is why the correct answer lists egg, larva, pupa, and adult. The other terms don’t fit this group: a chrysalis is the butterfly/moth pupal form, not a blow fly, and a nymph represents an immature stage in insects with incomplete metamorphosis, which also lacks a pupal stage.