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.

Q: Category: FEMALE SINGERS 
Clue: She's tied with Mariah Carey for most no. 1 hits by a female with 18: 12 as a member of a group & 6 as a solo act

A: diana ross
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Q: Category: MILITARY HISTORY 
Clue: Lasting about a month, it's the battle for which the most marines earned the Medal of Honor

A: iwo jima
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Q: Category: CLASSICAL MUSIC 
Clue: 1 of the 2 planets of the solar system not represented in Gustav Holst's 1916 work "The Planets"

A:
1 of
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