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: goat, stingray, tiger, hike, fish

Ex Output:
hike


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

Ex Output:
vitamin c


Ex Input:
Category: body part 
Words: kilometer, ankle, knee, foot, ear

Ex Output:

kilometer