Answer
The helical coil compresses.
Work Step by Step
Parallel wires that carry current in the same direction attract one another.
Assume the coil is oriented along a vertical axis. Every segment of the coil has 2 nearby elements of the coil carrying a parallel current, one above and one below, that attract it. The effects on that segment of the other parts of the coil either cancel due to symmetry, or are weaker due to distance. The net effect is that the loops of the helical coil attract one another and the spring compresses.
