is it china is the country of most badminton player come from?  

Yes, I agree. China are extremely good at badminton. I can only think of a few reasons why, as there have a huge population, there international team must pass a very strong challenge, as they will only take the best out of the best. And these sports tend to go well with the Chinese as it is there culture an mentality to have good concentration and stamina.

i agree with ur opinion. China has many badminton players, whether senior or junior players. see the latest world ranking, top ten players is dominated by players from China. from time to time, they have various efforts to find and train young players that talented to continue their country's glory in badminton. many other countries have taken efforts to strengthen their badminton squad, for example Malaysia, Indonesia, Denmark and others. i believe other countries will not let China continue to dominate this sport.

yes it is.