This is not something where you support the game that you play but what you think is the best/greatest sport played in the world. The criteria for measuring this is up to you. It could be based on pure dexterity, physical challenge, strategy, national or international coverage or just pure awesomeness.
For example I play football (soccer) but I think Rugby is an awesome sport. It's a fast paced game with a whole lot of skill involved and there is lots of variation to it like rugby union and rugby league.
For example I play football (soccer) but I think Rugby is an awesome sport. It's a fast paced game with a whole lot of skill involved and there is lots of variation to it like rugby union and rugby league.