Babies love toys such as shape sorters, cabinetsthat open and close, pocketbooks with hidden

treasures, and adults who play peek-a-boo with them.

All of these help children to develop
which concept that allows them to see that things that are out of sight are not gone forever?
a. Object permanence
b. Deferred imitation
c. Object concept
d. Violation of expectations

a. Object permanence