Under the Fair Housing Act, which of the following is NOT a prohibited basis of discrimination?

The Fair Housing Act is designed to eliminate discrimination in housing based on specific protected categories. These categories include race, color, national origin, religion, sex, familial status, and disability.

Marital status, while an important factor in many contexts, is not one of the classes explicitly protected by the Fair Housing Act. Therefore, it is permissible to legally differentiate based on marital status in matters of housing, which makes it the correct choice for this question.

In contrast, race, sex, and disability are all protected characteristics under the Fair Housing Act. Discrimination on these bases is illegal, meaning landlords and housing providers cannot refuse to rent or sell housing, or impose different terms and conditions, based on these characteristics.