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]: shareholders, alignment, firm, sustainability, solid
[A]: solid


[Q]: climbing, stingray, horse, fish, tiger
[A]:
climbing