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.

Example Input: Category: elements 
Words: ice, air, fire, hire, combustion
Example Output: hire

Example Input: Category: secretary duty 
Words: organize, support, text, sort mail, file
Example Output: text

Example Input: Category: emotional status 
Words: money, alert, calm, fine, happy
Example Output:
money