Answer:
Using symbols
Explanation:
Piaget was a Swiss Psychologist who came up with the Development Stages theory.
It is divided into four stages
sensorimotor stage is between birth months and 2 years. The development will begin with simple reflexes.
It advance to the infant developing abilities to use primitive symbols and it is the beginning of true creativity.
Therefore, Avery would consider using symbols the highest accomplishment of the sensorimotor period of development.
