Powell and Stein point to evidence that indicates that sexual orientation is likely to be a product of

A) genetics only.
B) environment only.
C) both genetics and environment.
D) either genetics or environment, but not both.

Powell and Stein suggest that sexual orientation is likely a result of both genetics and environment. This means that multiple factors likely contribute to a person's sexual orientation, including genetic predispositions and environmental influences such as upbringing, cultural norms, and personal experiences.