Which developmental stage are adolescents in, according to erikson? initiative vs. guilt mastery vs. shame identity vs. identity diffusion intimacy vs. isolation

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What is the first stage of psychosocial development according to Erikson?

Erikson's first psychosocial crisis occurs during the first year or so of life (like Freud's oral stage of psychosexual development). The crisis is one of trust vs. mistrust. During this stage, the infant is uncertain about the world in which they live.

Cite:https://www.google.com/search?q=Which+developmental+stage+are+adolescents+in%2C+according+to+Erikson...

The person who utilize the progression principle will keep adding the difficulty of the exercise that he's doing, while the person who does not, will only stay stagnant.  the person that utilize progression principle, will get a stronger endurance because now his body is conditioned to do harsher routines.{the answer was already on verified)