Explanation:

- Erik Erikson proposed a theory of psychosocial development that covers the entire lifespan.

- He identified a series of stages each individual passes through, with each stage facing a specific social and psychological conflict.

- These stages are essential for personality and social development from infancy to old age.

- ?? Option 1: Four stages – This is incorrect, as Erikson outlined more stages.

- ?? Option 2: Six stages – Also incorrect, as it's less than the actual number.

- ?? Option 3: Eight stages – This is correct. Erikson believed there are eight distinct stages, from trust vs. mistrust in infancy to integrity vs. despair in old age.

- ?? Option 4: Ten stages – Incorrect, as Erikson’s model does not reach ten.