TASK DEFINITION: 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.
PROBLEM: Category: AFRICA 
Clue: Equatorial Guinea is the only African nation whose offical language is this

SOLUTION: spanish

PROBLEM: Category: TRINIDADIAN AMATEUR ICHTHYOLOGISTS 
Clue: This common aquarium fish was named for a Trinidadian clergyman

SOLUTION: guppy

PROBLEM: Category: THEATRE 
Clue: The 1996 musical "Play On!" gets its title from the first line of this Shakespeare play, on which it is based

SOLUTION:
\"twelfth night\"