Research with twins and adoptive brothers by Bailey and Pillard (1991)suggests that
A)genetic factors absolutely determine sexual orientation.
B)genetic factors play a role in determining sexual orientation.
C)social learning factors absolutely determine sexual orientation.
D)genetic factors play a negligible role in determining sexual orientation.

Question

Quizplus · Accepted Answer

Bailey and Pillard's research with twins and adoptive brothers suggested that genetic factors play a role in determining sexual orientation. This was based on the finding that identical twins were more likely to share the same sexual orientation than fraternal twins, and that adoptive brothers who were not biologically related were no more likely to share the same sexual orientation than two random people. However, it should be noted that genetic factors do not completely determine sexual orientation, and that other factors such as environmental and social influences also play a role.

Research with Twins and Adoptive Brothers by Bailey and Pillard