Which is a particle application application of freezing-point depression

a. Cooling a supersaturated sugar-and-water solution to form rock candy.
b. Heating a sidewalk to melt snow that falls onto it.
c. Chopping a block of ice into small pieces to make it melt faster.
d. Sprinkling salt on ice to amok the ice melt.

d. Sprinkling salt on ice to amok the ice melt.

This is because the salt lowers the freezing point since solutes lower the freezing point of a pure substance.