Identical Twins Raised in the Same Homes Have IQs Correlated

Multiple Choice

Identical twins raised in the same homes have IQs correlated at about.86. Identical twins raised apart have IQs correlated at about.75. Unrelated adopted children raised in the same home have IQs correlated at about.32. Based on this information and research on the heritability of intelligence, we can say that ___________________ of the population variability in intelligence can be attributed to the environment.

A) between a quarter and a third
B) half
C) most
D) little than a quarter
E) more than half