Twin studies have found that some psychological traits, such as intelligence, have a notable genetic contribution. This can be concluded from what evidence?
A)The similarity of identical twins is greater when they are reared apart than when they are reared together.
B)The similarity of fraternal twins raised together is greater than the similarity of identical twins raised apart.
C)The similarity of identical twins raised apart is greater than the similarityof fraternal twins raised apart.
D)The similarity of identical twins is essentially equal to that of fraternal twins.

Question

Quizplus · Accepted Answer

The correct answer is C because identical twins share 100% of their genes, and if they show greater similarity in psychological traits even when raised apart compared to fraternal twins (who share only about 50% of their genes), it suggests a significant genetic contribution to those traits.

Twin Studies Have Found That Some Psychological Traits, Such as Intelligence