A person who maliciously destroys by fire
A
Antagonist
B
Activist
C
Terrorist
D
Incendiary
Correct Answer: Incendiary
One word substitute is Incendiary.Antagonist: a person who actively opposes or is hostile to someone or something; an adversary.
Activist: a person who campaigns to bring about political or social change.
Terrorist: a person who uses unlawful violence and intimidation, especially against civilians, in the pursuit of political aims.
Incendiary: a person who starts fires.