Which type of survey data involves non-numerical responses?

Categorical data is characterized by non-numerical responses and includes information that can be grouped into categories or classifications. This type of data does not involve numerical values but rather represents qualities or characteristics. For instance, survey responses such as "yes" or "no," "satisfied" or "dissatisfied," or demographic information like gender or ethnicity fall into the categorical category as they define distinct groups.

In contrast, numerical data comprises quantitative values that can be measured and expressed in numbers, allowing for arithmetic operations. Within numerical data, there are further distinctions such as ordinal data, which, while ordered, are still expressed categorically and do not possess a true numerical scale. Discrete data, on the other hand, represents countable quantities and is a subset of numerical data.

Thus, selecting categorical accurately identifies the type of survey data that involves non-numerical responses, making it the correct choice.