—Waiter, ________?

—Wait a minute, sir. That’s $ 80 altogether.

A．would you charge me

B．how much did we eat

C．may I have the bill, please?

D．would you take the money

从司钻控制台上操作半封闸板防喷器时，管汇压力下降后又升至正常值。储能器压力下降3.1MPa但未回到正常值。问题的原因是什么？（）

A、未操作三位四通换向阀。

B、储能器充压泵失灵。

C、防喷器液控油管线漏油。