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

Category: FROGS 
Clue: Probably best known to TV viewers as Valene Ewing, she had female lead in 1972 “Frogs”
joan van ark

Category: "BRAIN" SURGERY 
Clue: Rhyming term for a loss of intellectual talent to another company or country

brain drain