The correct answer highlights the protections provided under the federal Fair Housing Act, which specifically addresses discrimination based on certain characteristics. Mobility and visual impairments fall under the category of disability, a protected class under the Fair Housing Act. This means housing providers must make reasonable accommodations for individuals with physical or mental impairments, ensuring they have equal access to housing.
Other conditions listed, such as age and marital status, while they may be protected under certain state and local laws, are not specifically covered by the federal Fair Housing Act. Similarly, pregnancy and family status are explicitly protected but are distinct from mobility and visual impairments as it relates to disability considerations. Occupation and income level do not serve as protected categories under the federal law, focusing instead on aspects such as race, color, national origin, religion, sex, familial status, and disability.