The genetic influence on sexual orientation has been supported in research suggesting that:
A) parents cause their children to be either heterosexual or homosexual
B) homosexual men have larger areas in their hypothalamus than do heterosexual men
C) homosexual men have fewer chromosomes and genes than do heterosexual men
D) among identical twins, if one sibling is homosexual, the other has between a 31 and 65 percent chance of being homosexual

Question

Quizplus · Accepted Answer

Research on identical twins has found that if one sibling is homosexual, the other has between a 31 and 65 percent chance of also being homosexual. This suggests a genetic influence on sexual orientation. Options A, B, and C are not supported by current research.

The Genetic Influence on Sexual Orientation Has Been Supported in Research