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.

Input: Consider Input: Category: type of rigidity 
Words: rigged, firm, unyielding, streamline, taut

Output: streamline


Input: Consider Input: Category: temperature 
Words: cold, cool, icy, assured, mild

Output: assured


Input: Consider Input: Category: animal 
Words: ant, walk, bike, fly, dangle


Output: bike