Synonym of INFERNAL

Answer: Option C

Exacting : making great demands on one's skill, attention, or other resources.
Hateful : arousing, deserving of, or filled with hatred.
Devilish : like or appropriate to a devil in evil and cruelty.
Damaging : causing physical damage.
Infernal : relating to or characteristic of hell or the underworld.

Synonym of Infernal is Devilish