What does the CLASS statement in PROC MEANS allow you to do?

The CLASS statement in PROC MEANS is specifically designed to handle categorical variables by allowing you to produce separate summary statistics for each category. When you use the CLASS statement with PROC MEANS, you can specify one or more categorical variables, and the procedure will calculate the requested statistics (such as mean, median, count, etc.) for each distinct value of those categorical variables. This is extremely useful for analyzing data where you need to see how different groups (e.g., by gender, region, or any other categorical attribute) compare in terms of numeric outcomes.

For example, if you wanted to analyze the average sales amount by different regions, you could use a CLASS statement with the region variable to get the average sales for each region separately. This helps in understanding variations within categories and is a key feature of the CLASS statement.

The other options do not accurately describe the functionality of the CLASS statement. They pertain to different capabilities, such as sorting results or modifying how data sets are combined, which are not applicable in this context.