In a SAS DATA step, what would be the result of executing code using the _NULL_ data set?

When using the NULL data set in a SAS DATA step, the primary purpose is to allow for processing without creating an output dataset. This means that any data manipulation or calculations performed during that DATA step do not result in a new data set being created in the WORK library or any other specified location. Instead, the code can be used for purposes such as generating reports, writing data to external files, or performing calculations that do not require output storage.

The NULL data set serves as a tool for executing code without needing to produce a traditional data output. As such, any variable assignments, or calculations performed will be executed in memory but not saved as a permanent or temporary dataset.

Other options do not reflect the purpose of using NULL. The idea that a new dataset will always be created contradicts the function of NULL. Termination of the program with an error is unlikely unless there are other syntax or logical issues present in the code. Lastly, the notion that it will only store the last variable in memory does not accurately describe the behavior of the NULL data set, as it can process and evaluate multiple variables, though it doesn't create any output dataset to store them permanently.