instruction:
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.
question:
Category: physical activity 
Words: drop, fall, leaves, bend, exercise
answer:
leaves


question:
Category: aesthetic characteristic 
Words: pretty, probation, neat, fine, level
answer:
probation


question:
Category: elements 
Words: ground, replace, combustion, flame, fire
answer:

replace