China Mobile has to face the problem that more and more people in China prefer to choose ______ cheaper wireless phone service known as ______ “Little Smart”.

A．a; the

B．a; 不填

C．the; 不填

D．the; the

在注水泥塞过程中，由于高密度的水泥浆泵入，造成（）不平衡。

A、流压

B、静压

C、油套压力

D、地层压力