The environmental influence that has the clearest, most profound effect on intellectual development is a. exposing normal infants to enrichment programs before age 1. b. growing up in an economically...

The environmental influence that has the clearest, most
profound effect on intellectual development is
a. exposing normal infants to enrichment programs before
age 1.
b. growing up in an economically disadvantaged home or
neighborhood.
c. being raised in conditions of extreme deprivation.
d. being an identical twin.