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: WORLD LEADERS 
Clue: At his 1994 inaugural, he called for "a rainbow nation at peace with itself and the world"
nelson mandela

Category: SPORTS BOOKS 
Clue: In 1998 the author of this controversial 1970 book was finally invited to play in a Yankees old-timers' game
\"ball four\"

Category: FAMOUS PRODUCTS 
Clue: First designed as a surgical disinfectant, in 1895 it was available to dentists & by 1914 was sold OTC

listerine