Object permanence is the understanding that :a. Developmental stages occur in a

c. Things continue to exist even when they are not perceived.

Explanation:

According to Piaget, The term "object permanence" is used to describe a child's ability to know that objects continue to exist even though they can no longer be seen or heard. For example, if you place a toy under a blanket, the child who has achieved object permanence knows it is there and can actively seek it but at the beginning of the development stage, the child felt the blanket has disappeared.

c. Things continue to exist even when they are not perceived

Explanation: Object permanence is the understanding that things continue to exist even when they are not perceived (seen, heard, touched, smelled or sensed in any way). The concept was developed by developmental psychologist Jean Piaget and it addresses the development of young children's social and mental capacities therefore playing a significant role in the cognitive development of children. The reactions of infants that had already started developing object permanence were of frustration, while those of infants that had not yet started developing object permanence was more of oblivion. That is to say that if a hidden object is searched for, it was assumed that the infants believed it continued to exist.