TASK DEFINITION: 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.
PROBLEM: Category: consumer product 
Words: jealous, content, merchandise, jewelry, shop

SOLUTION: jealous

PROBLEM: Category: bird 
Words: crane, hoist, egret, tackle, ostrich

SOLUTION: hoist

PROBLEM: Category: elements 
Words: pay, cool, combustion, air, fire

SOLUTION:
pay