According to psychologist Jean Piaget, toward the end of the second year of life, children begin to use words as mental symbols and to form mental images. He referred to this as the .

preoperational stage                                                                  

Explanation:

Preoperational stage: In psychology, the term "preoperational stage" is one of the stages in the theory of cognitive development which was introduced by Jean Piaget. The preoperational stage starts at two years of a child's life and lasts through the age of seven of his or her life.

According to Piaget, in this stage, a child is being engaged in symbolic play, starts talking, manipulates different symbols, animism, irreversibility, etc.

In the question above, the given statement signifies the "preoperational stage".

answer; ///self- learning;

answer; narrator;