The reason _____ he could not go there was _____ his grades were too low. 

A．why ; because

B．that; because

C．why; that

D．that; that

护理法洛四联症患儿，要注意保证入水量，其目的是防止（）。

A.血压下降

B.心力衰竭

C.脑血栓

D.肾功能不全

E.感染性心内膜炎