Which of the following is NOT an official game in Nintendo's Super Smash Bros. series?

Super Smash Bros. Crusade is not an official game in Nintendo's Super Smash Bros. series because it is a fan-made game created by independent developers. Unlike the officially released Super Smash Bros. games, which are developed and published by Nintendo, Super Smash Bros. Crusade is a fan project that is not endorsed or recognized by Nintendo. Therefore, it does not have the official support and collaboration that the other games in the series receive from Nintendo, making it not an official game in the Super Smash Bros. franchise.