How many times can the DATALINES statement be used in a single DATA step?

The DATALINES statement in SAS is used to provide data directly within a DATA step. Importantly, it can only be employed once per DATA step. When you use the DATALINES statement, it signals the beginning of data entry, and SAS will continue to read the lines following this statement until a semicolon on a line by itself is encountered, indicating the end of the data.

This limitation ensures that the data for that particular DATA step is distinct and contained, which helps maintain a clear structure within the code. If additional data is needed in the same DATA step, you would typically use an infile statement to read data from an external source, or you would have to create a new DATA step for any additional DATALINES input.

This understanding clarifies why the answer specifies that the DATALINES statement can be utilized only once in a single DATA step.