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.

Category: UNITS OF MEASURE 
Clue: The scale on the bottom of a sextant is in these units
degrees

Category: ANCIENT TIMES 
Clue: Because of his work there, you could call the astronomer Hipparchus "the colossus of" this island
rhodes

Category: AFRICAN-AMERICANA 
Clue: Frederick Douglass said this political party was the ship & everything else was the ocean

the republican party