Elastic force: Elastic is the ability of a material to return to its original shape after being compressed or stretched.
The more the elastic is stretched, the more force it exerts to return back to its original shape.
In the given problem, Maurice pulls on the end of a spring scale. He lets go of the end and observes the spring snap back into place. The elastic force restores the spring to its original shape.
As a box A has a smaller average density than box B, then it will have a greater acceleraton towards the surface upon releasing. So the option E) Box A is a correct option.
