Final answer:
Metamorphosis is the phenomenon responsible for the difference between a caterpillar and its adult form, which is a butterfly.
Step-by-step explanation:
The phenomenon responsible for the difference between a caterpillar and its adult form, which is a butterfly, is metamorphosis. Metamorphosis is a biological process in which an animal undergoes a distinct change in form and structure during its lifecycle. In the case of a butterfly, the caterpillar undergoes metamorphosis to transform into a pupa (chrysalis) and finally emerges as an adult butterfly. This transformation involves significant changes in body structure, organs, and behavior.
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