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.
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Question: Category: THE GENTLE ART OF RUGBY 
Clue: This position is the last line of defense; in the NFL it's the offensive role of Larry Csonka & Moose Johnston

Answer: the fullback


Question: Category: "M.C." 5 
Clue: Edgar Degas' style influenced that of this female American Impressionist

Answer: mary cassatt


Question: Category: READING RAINBOW 
Clue: In "Meanwhile Back at the Ranch", Elna Hicks starts to dig for potatoes & gets rich by striking this liquid

Answer:
oil