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.

Ex Input:
Category: type of rigidity 
Words: tough, taut, rough, amalgamated, firm

Ex Output:
amalgamated


Ex Input:
Category: emotional status 
Words: content, hearing, fine, happy, alert

Ex Output:
hearing


Ex Input:
Category: moral characteristic 
Words: fair, unprejudiced, impartial, honorable, variety

Ex Output:

variety