Psych a 20 year old college student is heterosexual his brother brett is homosexual the brothers obviously differ in their

sexual orientation.

Explanation:

sexual orientation -

It refers to the identity of a person to get attracted to a male, female or both, is referred to as sexual orientation.

The process is gender dependent practice.

Where a homosexual person is supposed to be attracted to people of same gender,

where as a hetyerosexual person gets attracted to opposite gender.

And,

Bisexual is supposed to get attracted to both the gender.

Hence, from the given scenario of the question,

The correct answer is sexual orientation.