The idea that even if an object changes shape or appearance the underlying quantity of the object remains the same is Piaget's principle of

A) object permanence.
B) conservation.
C) irreversibility.
D) assimilation.

The principle of conservation is the idea that even if an object changes shape or appearance the underlying quantity of the object remains the same. This concept is an important part of Piaget's theory of cognitive development. Object permanence refers to the understanding that objects continue to exist even if they are hidden from view. Irreversibility refers to the inability to reverse a sequence of events or actions. Assimilation is the process of incorporating new information into existing schemas.