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: animal 
Words: walk, flap, fish, fly, bats

Ex Output:
flap


Ex Input:
Category: physical property 
Words: fat, vitamin c, area, brittleness, absorption

Ex Output:
vitamin c


Ex Input:
Category: personal characteristic 
Words: ethical, relaxed, relaxing, unflappalbe, cool

Ex Output:

relaxing