The answer is "b) overestimated preschoolers' egocentrism".
Egocentrism is simply the powerlessness to separate and other. More particularly, it is the powerlessness to unravel abstract patterns from target reality and a failure to comprehend or expect any viewpoint other than one's own.
It is thought that Piaget overestimated the degree of egocentrism in kids. Egocentrism is hence the youngster's inability to see other individuals' perspectives, not to be mistaken for self-centeredness. The tyke at this phase of psychological improvement accept that their perspective of the world is the same as different people groups.