Question

on which four stages life span is depended expalin it

Answer 1

Infancy, Childhood, Adolescence, Older Age.
Infancy------Birth-two years. While the infant is dependent on adults for most things, many psychological characteristics are rapidly developing. 
Childhood------------Two-ten years. During this stage, children become increasingly independent from their parents as they learn to do things themselves and gain more self-control.
Adolescence---------Ten-twenty years. The onset of puberty marks the beginning of adolescence.
Older Age--------------Sixty five years plus. A period of considerable adjustment to changes in one's life and self-perceptions.