Drag-and-Drop Matching Question
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Author: Adriane Boyd (adrianeboyd@gmail.com)

Description:

The drag-and-drop question is adapted from the existing matching question. 
The teacher editing interface and the grading have not been modified. The 
fallback looks identical to the original matching question.

The drag-and-drop version of the student interface provides all the 
answers in a list to the right of the question table.  Answers can be 
dragged from the list to each of the question targets.  The current target 
is highlighted to show where the answer will be dropped.  To allow answers 
to be used multiple times, dragging an answer from the list on the right 
to a target puts a copy of the answer in the target.  The current answer 
for a question can be changed by dragging the answer off the target or by 
dropping another answer on the target.

Grading:

The grading is identical to the original matching question.