用分枝定界法求极大化的整数规划问题时，任何一个可行解的目标函数值是该问题目标函数值的（）
参考答案：下界
如何实施护理计划？
After quarreling with her best friends, Mary has got herself into a situation______ she is likely to turn to nobody for help.
A．where
B．which
C．while
D．why
