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.
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Question: Category: HUMANITARIAN LADIES 
Clue: Throughout the 1930s, she taught geography at St. Mary's High School in Eastern India

Answer: mother theresa


Question: Category: LADIES' LOCKER ROOM 
Clue: Born in Mannheim, Germany in 1969, she's one of only 5 tennis players in history to win a Grand Slam

Answer: steffi graf


Question: Category: MEASURE FOR MEASURE 
Clue: In viscosity ratings, the "W" in 10W-40 means 10 is the winter grade rating of this liquid

Answer:
motor oil