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: LITERATURE
Clue: Chingachgook became the last of the Mohicans when this man, his son, died

Answer: uncas

Question: Category: HISTORY
Clue: In June 1987 she became the first British prime minister in the 20th c. elected to 3 straight terms

Answer: margaret thatcher

Question: Category: ROCKS FOR JOCKS
Clue: Slate is this type of rock, the result of alterations to existing rocks

Answer:
metamorphic