What cognitive development stage, according to Piaget, involves understanding the concept of conservation?

The correct understanding of cognitive development stages according to Piaget highlights that the concrete operational stage is when children begin to grasp the concept of conservation. This stage typically occurs between the ages of 7 and 11 years. Conservation refers to the understanding that certain properties of objects, such as volume, mass, and number, remain the same despite changes in the forms or arrangements of those objects.

For instance, if a child sees that a ball of clay can be flattened into a pancake shape, they start to recognize that the amount of clay remains unchanged regardless of its shape. This cognitive skill reflects more advanced logical reasoning capabilities that are characteristic of the concrete operational stage, where children begin to think logically about concrete events and can manipulate information mentally.

The other stages—sensorimotor, preoperational, and formal operational—do not encompass the ability to understand conservation. The sensorimotor stage focuses on early learning through interaction with the environment. The preoperational stage, occurring just before concrete operational, is characterized by egocentrism and an inability to perform operations mentally; while children are imaginative and engaged in symbolic play, they do not yet understand conservation. Lastly, the formal operational stage, which begins in adolescence, encompasses abstract and hypothetical reasoning beyond logical manipulation