This question is incomplete, here´s the complete question
Which synonym best describes a person who is not upset during a loud and angry discussion?
Gentle: lacking harshness or roughness
Quiet: not making noise
Restful: peaceful and quiet in a relaxing way
Unruffled: calm during times of confusion
Answer: Unruffled
Step-by-step explanation:
While the other options do refer to a state of calmness, they don´t inherently provide any connection to a stressful situation such as an intense and impassioned argument.
Only "Unruffled" implies that that state of tranquility happens in the middle of a surprising or frightening event.
Saying that someone remains unruffled, means that even under a stressful situation they don´t seem to be affected.