How do you select and delete rows in SAS?

To select and delete rows in SAS, the correct approach is to use the syntax where a condition is specified with an IF statement, followed by the DELETE statement. In this context, the appropriate format is the expression that indicates if the condition is true, the row will be deleted from the dataset.

The correct answer emphasizes that when the condition specified in the IF expression evaluates to true, the corresponding observation will be removed from the dataset during the data step. This is an efficient way to filter out unwanted data directly within the data step processing, ensuring that only the desired rows are retained in the output dataset.

The other options present variations that do not align with the expected syntax in SAS. For instance, the option suggesting an explicit "SELECT row" does not follow standard SAS language conventions, as SAS does not utilize a SELECT statement in this context for data manipulation. Instead, it leverages the DELETE statement to remove rows based on conditional logic. Similarly, the format of the other options does not accurately represent valid SAS syntax, which is critical for successful execution and achieving desired data outcomes.