China can't control bitcoin, it is freely tradable so any people can just buy it.
BTW, I heard that CIA or FBI has a big chunk of it, as they are kinda involved in the beginning... which is scary.
I think China can control bitcoin because users from China more than 51% of the total bitcoin stok, we can see from exchanger from China always infect the bitcoin price.
No, even China has that percentage of total stock of bitcoin or most of the miners are found there. Still they don't have control for bitcoin but they can do something to make some waves on the changes of bitcoin but that is not going to be effective immediately. The effects of their contribution within the price of bitcoin is happening slowly and not that very fast.
We, the users are actually the one who's controlling bitcoin, though they have the stocks but without demand the would not benefit it. They are taking bigger risk because they know base on their speculation that bitcoin is going to be big time in the future.