__________ it is true that a student’s most important goal is to do well in his or her studies, it doesn’t need to be the only goal.

A．While

B．As

C．When

D．Before

女，18岁。低热、腹痛、腹泻伴腹胀2个月。查体：腹壁揉面感，移动性浊音阳性。腹水为渗出液。最有价值诊断的检查是（）

A.血培养

B.腹水细菌培养

C.卡介苗试验

D.血沉

E.腹膜活检