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: geographical property 
Words: flat, horizontal, smooshed, elevation, house

Answer: house


Question: Category: computers 
Words: prepare, space, file, image, ram

Answer: prepare


Question: Category: boats 
Words: lifeline, blocking, rudder, stern, deck

Answer:
blocking