油田注水的主要目的，一是通过改善注入水的水驱效果不断提高各类油层的（）和波及系数，从而提高油田的水驱采收率；二是保持油层能量，使采油井具有足够的生产能力。

A.水驱效率

B.水驱面积

C.油层体积

D.油层厚度

Which of the following statements is true according to what you have heard

A．I will eat lunch very quickly.

B．I will have lunch before the meeting.

C．I will eat lunch at the meeting.

D．I will eat lunch while jogging.