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.
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Question: Category: aesthetic characteristic
Words: comfortable, pretty, there, fine, classy

Answer: comfortable

Question: Category: activity
Words: spend, divide, apple, whittle, fritter

Answer: apple

Question: Category: personal characteristic
Words: popular, chill, unflappalbe, optimist, cool

Answer:
chill