China is not the cause of people selling bitcoin. The words of a CEO who leads the nation's largest bank in the United States is the real cause. He had a loud voice that bitcoin was a hoax, with his status, his words influenced everyone, so they sold the bitcoin in a panic way.
Do you really belive this? I'm assuming that you are talking about JP Morgan CEO, Jamie Dimon. This dinosaur couldn't move the cryptocurency market a few cents with his statement. He called bitcoin a scam, so this proves how little does he understand about the new economy.
On the other hand, when Wall Street says that something's a scam (to be translated as something that they can't controle), than you know that you have to buy.