When a movable piece is associated with “None,” it means that it does not belong in any drop zone. This means that a student will get the feedback that they placed the piece in the incorrect spot anytime it is placed into a drop zone.
When a movable piece is associated with “All,” it means that it can be placed in any drop zone for the student to get the correct answer. This means that a student will get the feedback that they placed the piece in the correct spot anytime it is placed into a drop zone.