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: bird 
Words: goose, hoist, neck, swallow, crane
Example Output: hoist

Example Input: Category: shady activities 
Words: banned, replace, smear, chocolate cake, fudge
Example Output: chocolate cake

Example Input: Category: window material 
Words: wood, handle, knifer, panel, glass
Example Output:
knifer