Alibaba (BABA), Yum China Holdings (YUMC), ACM Research (ACMR), Baidu (BIDU), and Pinduoduo (PDD) were among the Chinese stocks that got hammered in U.S. trading Thursday after the U.S. Securities and Exchange Commission put forward a list of five companies that could be delisted if they don’t measure up to U.S. accounting standards. The list was a first step in applying the Holding Foreign Companies Accountable Act, which became law on Dec. 18, 2020. The act requires foreign companies to make documents available for accounting...