Forgetting their old enmity, they joined hands with a spirit of camaraderie.

Answer: Option C

Animosity : strong hostility.
Love : an intense feeling of deep affection.
Friendliness : the quality of being friendly; affability.
Trust : firm belief in the reliability, truth, or ability of someone or something.
Camaraderie : mutual trust and friendship among people who spend a lot of time together.

Synonym of Camaraderie is Friendliness