Match items in one column to corresponding items in a second column. Answer these
questions by selecting
the appropriate match from a drop-down. 
Select the correct match from the drop-down. Select an answer for each item until all of the items are matched.
Important You must select an answer for each item. Submitting a matching question with
unfilled answer blanks causes correct matches to be scored incorrectly.
To reduce this issue's effect on student scores, consider using multiple choice instead of matching mode.