What type of data represents the qualities or categories of a variable?

The correct choice reflects the nature of nominal data, which represents qualities or categories of a variable without any inherent numerical value or order. Nominal data is used to classify variables into distinct groups, where each category is mutually exclusive and cannot be meaningfully ordered. Examples of nominal data include gender, ethnicity, or types of cuisine.

In contrast, ordinal data, while also categorical, possesses a clear order or ranking among the categories (such as a rating scale). Interval data and ratio data both involve numerical values with specific characteristics; interval data has equal intervals between values but lacks a true zero point, while ratio data includes a true zero point and allows for a full range of statistical operations. Thus, nominal data stands out as the appropriate representation for qualitative categories.