Given a category and a set of five words, find the word from the set that does not belong (i.e. is the least relevant) with the other words in the category. Words are separated by commas.
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Question: Category: bird 
Words: dump truck, pelican, goose, crane, derrick

Answer: dump truck


Question: Category: elements 
Words: ice, air, fire, hire, combustion

Answer: hire


Question: Category: weather 
Words: variety, fair, make the grade, tangle, stormy

Answer:
variety