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.

Example Input: Category: employment activity 
Words: scold, water, fire, praise, replace
Example Output: water

Example Input: Category: weather 
Words: brisk, ghostly, windy, fair, deal
Example Output: ghostly

Example Input: Category: nutritional value 
Words: vitamin c, protein, fat, skinny, big
Example Output:
skinny