Final answer:
Exfoliation is the process of softening and removing hardened sebum stuck in the follicles. It involves the removal of dead skin cells and unclogging of pores.
Step-by-step explanation:
The process of softening and removing hardened sebum stuck in the follicles is called exfoliation. Exfoliation involves the removal of dead skin cells and unclogging of pores, allowing for the release of sebum. This process can be achieved through various methods such as using exfoliating scrub, chemical peels, or retinoids.