Synonym of SEVERE

Answer: Option A

Rigid : not adaptable in outlook, belief, or response.
Aggressive : ready or likely to attack or confront; characterized by or resulting from aggression.
Offensive : causing someone to feel resentful, upset, or annoyed.
Sickening : causing or liable to cause a feeling of nausea or disgust.
Severe : demanding great ability, skill, or resilience.

Synonym of Severe is Rigid