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: animal 
Words: stingray, horse, iguana, wrestle, fish
Example Output: wrestle

Example Input: Category: outdoor sport activity 
Words: fish, hiking, row, shark, canoe
Example Output: shark

Example Input: Category: computers 
Words: format, fax, image, ram, file
Example Output:
fax