Answer: Sensorimotor stage
Explanation: Sensorimotor stage is the first stage of Piaget Cognitive development in children which usually occurs from birth to 2 years. During this stage , infants are only aware of what is immediately in front of them by focusing on movement sensations and physical interactions within their immediate environment which makes them to constantly experiment by shaking or throwing things, putting things in their mouths, and learning through sequential type of plays etc and they acquire knowledge through sensory experiences through reflexes and motor responses and by manipulation of objects.
Hannah who loves pee a boo with her aunt is most likely in the Sensorimotor stage of Piaget's stages of cognitive development