Final answer:
Certain insects, like butterflies, undergo metamorphosis and change from larva to pupa. In the case of the Karner blue butterfly, larvae change from white to dark brown as they become pupa.
Step-by-step explanation:
Larva of certain insects, such as butterflies, become pupa as part of their metamorphosis process. During this transformation, the larva goes through significant changes, including a change in color. In the case of the Karner blue butterflies mentioned in the provided information, the larva changes from white to dark brown when it becomes a pupa. The pupal stage is a dormant stage in which the insect undergoes internal changes to develop into an adult butterfly.