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: MEAN GIRLS 
Clue: This supernatural TV series was full of mean girls: Cordelia, the insane vampire Drusilla & Glory (a sort of evil god)
buffy the vampire slayer

Category: FAMOUS AMERICANS 
Clue: He once promised, "As long as there is imagination left in the world" his theme park would never be completed
walt disney

Category: CELEBRITY BOOKS 
Clue: Doing research on her grandfather led her to co-write the 1996 mystery novel "Murder at San Simeon"

patricia hearst