衰退行业中的竞争战略选择有观望战略、抽资转向战略、快速退出战略和()。
A.差异化战略
B.领先战略
C.密集增长战略
D.市场渗透战略
参考答案:B
始祖鸟化石是______类进化成______类的证据.
Mary’s red face suggested that she_______shy, and her friends suggested that she______a deep breath.
A.be; should take
B.was, take
C.should be; took
D.was; takes