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 property 
Words: brittleness, large, fat, area, calcium

Ex Output:
calcium


Ex Input:
Category: outdoor sport activity 
Words: dog, swim, hike, hiking, fish

Ex Output:
dog


Ex Input:
Category: direction 
Words: emotional state, backward, forward, up, down

Ex Output:

emotional state