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: current, timely, prompt, drink, do tests

A: drink
****
Q: bike, beetle, leap, ant, fly

A: bike
****
Q: fire, instruct, inferno, retire, scold

A:
inferno
****