It is reported that the floods have left about ________ people homeless.
A.two thousandB.two--thousandsC.two thousandsD.two thousands of在线课程A
解析：
句意：据报道洪水已经使大约两千人无家可归。当dozen, score, hundred, thousand, million前有具体数字时，都要用单数形式。故A为正确答案。