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: secretary duty 
Words: correspondence, schedule, answer calls, keys, file

Output: keys


Input: Consider Input: Category: police punishment 
Words: prison, fine, calm, money, suspension

Output: calm


Input: Consider Input: Category: animal 
Words: walk, run, flutter, fly, waggle


Output: flutter