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: fire, retire, ice, air, earth
Example Output: retire

Example Input: Category: aesthetic characteristic 
Words: fair, unprejudiced, level, tone, milky
Example Output: unprejudiced

Example Input: Category: secretary duty 
Words: type, answer, answer calls, program, file
Example Output:
program