Shares in many of China’s best-known companies plunged on the Nasdaq and New York Stock Exchange today as part of a steep selloff amid worries about rising interest rates and slower growth in the United States, the world’s largest economy. The Nasdaq lost 4.7% and S&P 500 lost 3.9% as U.S. stocks fell into bear market territory. Besides a possible slowdown in U.S. and global economic growth that would hurt exporters, China stocks have the added pressure of continued uncertainty about the pace of the country’s economic recovery from Covid lockdowns, particularly in Shanghai and Beijing, and the vulnerability of…