More signs of distress in China’s economy and rising bond yields led to a broad sell-off of stocks that left the market down 5.7% from its record high, set last month. Things were rough in the morning. An overnight plunge in China caused by a spike in lending rates led to declines in Europe. China’s Shanghai Composite index fell 5%, its biggest decline in four years. France’s benchmark index fell 1.7%, Germany’s 1.2 percent. US traders took one look at that and sold. The Dow fell as much as 248 in the first hour. The yield on the 10-year Treasury note spiked to its highest in almost two years as the sell-off brought down prices of US government debt.