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: concerned, strap lock, anxious, bored, fret

A: strap lock
****
Q: ostrich, hoist, egret, crane, parrot

A: hoist
****
Q: mice, goat, fish, swim, horse

A:
swim
****