You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For consistency, answers should be in all lower cased letters.

Q: Category: ENDS IN "FF" 
Clue: The heaviest of dog breeds, it can exceed 180 pounds

A: mastiff
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Q: Category: YOU NEED THERAPY 
Clue: In the hyperbaric type of this "therapy", the patient inhales the pure gas in a large chamber

A: oxygen
****
Q: Category: AT THE BUFFET 
Clue: You might start off with the peel-&-eat these; the cocktail sauce is on the left

A:
shrimp
****