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: physical property
Words: sugars, fat, thin, large, angular momentum

Output: sugars

Input: Consider Input: Category: physical property
Words: fat, heavy, ugly, capacitance, heavy
Output: heavy