identify which of Piaget's stages best fits the behavior being described:

In responding, please use the following:

Sensorimotor, Preoperational, Concrete Operations, Formal Operations

4. When I play hide-n-seek with my toddler, they often hide under their bed with their feet sticking out in the room. When I say, "ready or not here I come", they say "ready" not realizing that when I start searching I can easily see their legs coming out from under their bed. How is it that they do not understand how my view of them works???? What stage is this child in and what is the concept being referenced?