[BPS] Variables - 'Restriction of Selection Required by User'

The 'Restriction of Selection Required by User' check box.
If the box is checked, user must restricted the variable to
single entry. The data for processing will also be restricted
to only those data only.
If the box is not checked, it won't popup and window for selection.
But, you set the variable manully the data will be restricted to the selected value.
User need to reset the variable manully.