The nurse is admitting a client with a suspected fluid imbalance. The most sensitive indicator of body fluid balance is （）.

A．daily weight.

B．serum sodium levels.

C．measured intake and output.

D．blood pressure.

下面关于离心泵的说法错误的是（）

A.离心泵采用后弯叶片是为了提高效率.

B.离心泵可以封闭启动.

C.离心泵应采用止推轴承，以承担各种轴向力平衡装置不能完全平衡的轴向力.

D.离心泵的理论扬程与液体种类无关.