题目

   In 1989 an 8.2 earthquake almost flattened America, killing over 30,000 people in less than four minutes. In the middle of complete damage and disorder, a father rushed to the school where his son was supposed to be, ___46__ that the building was __47__. After the unforgettably shock, he __48__ the promise he had made to his son: No matter _49__, I'll always be there for you! And tears began to __50__ his eyes. As he looked at the pile of ruins, it looked hopeless, but he kept remembering his __51__ to his son. He rushed there and started __52__ the ruins. As he was di关于的不等式()的解集为,且,则（     ） A．         B．          C．      D．