A specific phase or period when the presence of a function or reasoning has its greatest effect on a specific aspect of development is referred to as:

A) Freud's psychoanalytic model of personality.
B) a critical period of development.
C) Erikson's stages of development.
D) Piaget's theory of cognitive development.

A critical period of development refers to a specific phase or period when the presence of a function or reasoning has its greatest effect on a specific aspect of development.For example,if a child does not walk by 20 months,there is delayed gross motor ability,which slows exploration and manipulation of the environment.Freud's psychoanalytic model of personality development is grounded in the belief that two internal biological forces drive the psychological change in a child: sexual (libido)and instinctive forces.Erik Erikson (1902-1994)expanded Freud's psychoanalytic stages into a psychosocial model that covered the whole life span.In this theory,Erikson divided life into eight stages,known as Erikson's eight stages of development.Jean Piaget (1896-1980)developed the theory of cognitive development,which describes children's intellectual organization and how they think,reason,and perceive the world.