——Do you have any idea when the project will be carried out?

—No, but I have heard that it was not until last month _______ it was approved.

A．that

B．when

C．since

D．before

管型形成的条件包括()

A．原尿中有清蛋白和TH蛋白

B．肾小管有酸化和浓缩尿液的能力

C．尿液流动加速

D．无局部尿液淤积

E．具有交替使用的肾单位