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: physical activity 
Words: run, jump, autumn, fall, swim

Ex Output:
autumn


Ex Input:
Category: type of sandwich 
Words: club, open-faced, convention, doorstep, roll

Ex Output:
convention


Ex Input:
Category: emotional display 
Words: social, pester, fawn, buck, paw

Ex Output:

buck