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: DIRECTORS 
Clue: Biographer Donald Spoto says that as a schoolboy, this "Vertigo" director was nicknamed "Cocky"

Answer: alfred hitchcock


Question: Category: 20TH CENTURY AMERICA 
Clue: On April 6, 1917 America entered World War I & this composer wrote "Over There"

Answer: george m. cohan


Question: Category: HISTORIC NAMES 
Clue: Nicknamed "Old Bruin", this U.S. Navy man shares his name with a TV "Friend"

Answer:
matthew perry