absolutely, china is controlling everything ongoing events on bitcoin. Both mining companies and big enterprisers are chinese. for that reasons, they are affecting the prices.
No, China doesnt control bitcoin, no one controls bitcoin. Because the number of Chinese who are using bitcoin is too high and the fact that China has many mining companies and biggest mining power, everything they do would surely affect the price of bitcoin but that doesnt mean they own all the bitcoin and have a right to put a stop to it anytime they want.