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: elements 
Words: let go, flame, inferno, fire, water

Ex Output:
let go


Ex Input:
Category: body part 
Words: heel, shin, pound, finger, foot

Ex Output:
pound


Ex Input:
Category: employment activity 
Words: let go, fire, remove, recruit, inferno

Ex Output:

inferno