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: physical activity 
Words: stoop, crouch, bow, duck, dog

Answer: dog


Question: Category: moral characteristic 
Words: frank, concise, bun, matter of fact, fortitude

Answer: bun


Question: Category: date status 
Words: current, prompt, moon, postponed, belated

Answer:
moon