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: high quality, ok, level, classy, fine

Answer: ok


Question: Category: physical activity 
Words: dog, push, duck, squat, jog

Answer: dog


Question: Category: social gathering 
Words: club, dance hall, discothek, meeting, submarine

Answer:
submarine