The correct answer is the s<span>ensorimotor stage of cognitive development.
According to Piaget's </span>theory of cognitive development, she is in the sensorimotor stage of development. During this stage of cognitive development-which occurs at age 0-2 years in infants- infants develop something known as <em>object permanence</em>. This means that infants develop the ability to understand that objects continue to exist even if they are hidden from them or no longer in view.
