Given the input data set WORK.

In the given DATA step, the do weeks=1 to 3; loop iterates three times for each row in the original WORK.RUN dataset, incrementing the miles value by 5 for each iteration and outputting a row after each increment. However, no output; statement is given within the loop to create the extra rows, which means only the last iteration of the loop will be outputted for each original row. Hence, the miles value for each name will be incremented by 15 (5 miles for each of the 3 weeks).

The original data set WORK.RUN has:

John 16

Mary 20

After the DATA step, it should be:

John 31

Mary 35

Each name appears only once because without an explicit output; statement inside the loop, only the final iteration is outputted. The variable weeks is not retained in the output dataset, as it is not used outside the loop and no output statement is used inside the loop. Thus, option D is correct.

References:

SAS documentation on DATA step processing, SAS Institute.