When a low carbon steel is undergoing heat treatment for the purposes of casehardening, what is the process that distinguishes this procedure from other hardening methods?

Correct Answer: Option A — After the steel is heated above its critical temperature, it is quenched in a carbon bath.

Casehardening is a process that increases the surface hardness of low-carbon steel while maintaining a tough, ductile core. By heating the steel and introducing it to a carbon-rich environment, carbon diffuses into the surface layer. Subsequent quenching creates a hard, wear-resistant outer 'case' suitable for gears and pins.