It is possible to mark any answer option, regardless of the answer text, as N/A so that selection of that option causes the question's points to be removed from scoring. It is also possible to mark more than one answer option as N/A.
 
To mark an answer option as N/A, simply check off the box in the column labeled "N/A" next to that answer option.
 
 

The scoring for such an arrangement, as expected, results in the points for the question being ignored when the N/A option is selected.
 
 

However, the N/A setting can be disabled for an answer option, so that points are scored for an N/A selection.
 
 

Now when the N/A option is selected, points are scored. Note that you do NOT have to turn off the "Omit N/A" setting on the Survey Settings page in order for this to work.
 
 

It is also possible to mark more than one option as N/A.