China’s interest-rate cuts Friday sparked the biggest one-day selloff in three weeks in the U.S. government debt market as global stocks rallied.

The news came one day after the European Central Bank signaled its willingness to expand monetary stimulus in coming months. Investors expect the Federal Reserve to hold short-term interest rates near zero next week. And speculation has been growing that the Bank of Japan, at its policy meeting at the end of this month, could pump more cash into its economy.

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