instruction:
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 simplicity, answers should be in all lower cased letters.
question:
Category: ANIMALS 
Clue: These mollusks, not oysters, are the most common source for freshwater pearls
answer:
mussels


question:
Category: THE LAST CATEGORY 
Clue: This "Home Run King" played in his 3,298th & last game for the Milwaukee Brewers in 1976
answer:
hank aaron


question:
Category: IT'S ALL ABOUT "U" 
Clue: These mystical scriptures of Hinduism date from about 900 B.C.
answer:

the upanishads