Which of the following is NOT a protected class under ECOA?

The correct answer is that hair color is not a protected class under the Equal Credit Opportunity Act (ECOA). ECOA prohibits discrimination in lending based on certain characteristics to ensure fairness in credit transactions. These protected classes include race, color, religion, national origin, sex, marital status, age, and the applicant's reliance on public assistance.

In contrast, hair color does not fall under these categories; it does not have a legal basis for discrimination in the context of lending practices. The ECOA is designed to safeguard individuals from being treated unfairly due to inherent or significant social factors, while hair color is not viewed as a relevant or significant factor in determining a person's eligibility for credit.

The other options provided—age, marital status, and national origin—are all recognized as protected classes under ECOA. Each of these characteristics can affect an individual's access to credit and is therefore covered under the regulation to prevent discrimination.