^ last year for the December single (Chance no Junban), the senbatsu was decided by janken (rock, paper, scissors). Basically, the girls had a tournament and played against one another for the top 16 spots. The winner was Uchida Mayumi, who had never participated in an a-side before - at least I don't think so .
They're gonna do this again this year! I'm excited. My oshi came 3rd... here's hoping she can do well again! Although it is down to luck.