Answer:
I want to say it is the middle layer. But not 100% sure. Sorry if its wrong.
<span>mitochondria ribosomes endoplasmic reticulum</span>
1 universe 2 stars 3 solar 3 planets
Object permanence is the developmental milestone that must be reached before an infant experiences separation anxiety. It is used to describe the ability of a child to know that objects continue to exist despite the fact that they can no longer be perceived that is , seen or heard, touched, smelled, or sensed in any way. This milestone is developed through touching and handling objects by the infants.