If We Study Identical Twins Who Have Been Separated at Birth

Multiple Choice

If we study identical twins who have been separated at birth and reared apart, we can

A) only test the importance of genetic endowment.
B) learn a lot more about intelligence than we can by studying the influence of the environment.
C) assess the relative contribution of heredity and environment.
D) say very little about the impact of heredity or environment on intelligence.