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The following SAS DATA step is submitted:
data sasdata.atlanta
sasdata.boston
work.portland
work.phoenix;
set company.prdsales;
if region = 'NE' then output boston;
if region = 'SE' then output atlanta;
if region = 'SW' then output phoenix;
if region = 'NW' then output portland;
run;
Which one of the following is true regarding the output data sets?

No library references are required.

The data sets listed on all the IF statements require a library reference.

The data sets listed in the last two IF statements require a library reference.

The data sets listed in the first two IF statements require a library reference.