题目

The student had no other choice but_____ his teacher _____the mistake he had made . A to apologize to ; for   B to apologize ; for C apologizing for ; to    D to apologize for ; for 答案：A室温下某溶液中由水电离产生的C（H+）=1.0×10-10mol/L，则该溶液的pH为（　　） A、10B、4C、7D、4或10