Most 4-year-olds respond that there is more apple juice in the tall, thin glass than there was in the short, broad one. In fact, if the juice is poured back into the shorter glass, they are quick to say that there is now less juice than there was in the taller glass. This is an example of

This is an example of conservation.

Explanation:

Conservation is one of Jean Piaget's developmental accomplishments, in which a child understands that changing the form of a substance or object does not change its amount, volume, or mass. This is typically accomplished between the operational stage of development around ages 7 to 11. Therefore, it is typical for 4-year-olds to not be able to comprehend the concept of conservation.

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