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: deck, sail, crew, head, fold

A: fold
****
Q: level, tone, fair, impartial, milky

A: impartial
****
Q: prime, penalty, fine, comfortable, prison

A:
comfortable
****