A bill becomes a law when it is enacted and a larva turns into a pupa.
A pupa is the life stage of some insects undergoing transformation between immature and mature stages.
This is an analogy since it is a comparison between one thing and another, typically for the purpose of explanation or clarification. It is a cognitive process of transferring information or meaning from a particular subject to another.
In order to complete this analogy, we need to look at these words first. A bill becomes a law in its "final form," so larva would become either pupa or insect.
