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: physical activity 
Words: dog, push, duck, squat, jog
Example Output: dog

Example Input: Category: secretary duty 
Words: file, errands, type, folder, order office supplies
Example Output: folder

Example Input: Category: physical activity 
Words: jump, fall, leaves, roll, swim
Example Output:
leaves