Given a set of five words, generate the word from the set that does not belong (i.e. is the least relevant) with the other words. Words are separated by commas.

[Q]: stingray, fish, camp, swim, hunt
[A]: stingray


[Q]: mad, beautiful, comfortable, fine, relaxed
[A]: beautiful


[Q]: burn, combustion, sack, cool, fire
[A]:
sack