It is ________ the pupils do in their spare time ________ really prepares them to take their place in society as citizens when they grow up.

A．which; that

B．that; what

C．what; that

D．that; which

关于肝脏的检查前准备及检查方法正确的是

A．患者检查前需禁食12小时

B．急症重症患者需禁食8小时

C．婴幼儿检查前应禁食3～5小时

D．一般采用的探头频率为5MHz

E．以上都不正确