The National Rugby League. It's Australia's professional Rugby League competition. Really, there's only two of any decent standard - Australia's NRL and Britain's Super League. But I have to ask - when you say the best rugby league, do you mean the best Rugby League competition or the best rugby union "league"? Rugby League and Rugby Union are two separate games. Rugby Union is the one most people outside of the UK and Australia are familiar with.
Dude, don't clarify! If he made the mistake then he has to deal with it. If he was asking about RL, good on him anyway.