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.

Category: LEADING MEN 
Clue: 1 of 2 actors who have earned acting Academy Award nominations in the last 5 consecutive decades
jack nicholson or michael caine

Category: SOUTH AMERICA 
Clue: Alphabetically, they're the first & last of the 7 countries where the Andes are found
argentina & venezuela

Category: ASTRONOMER'S DICTIONARY 
Clue: This word comes from a Greek phrase meaning "circle of animals"

zodiac