下面说法，错误的是（　　）

A．棱柱的截面可能是圆

B．一个平面截一个球，得到的截面一定是圆

C．三棱柱有五个面

D．一个平面截一个正方体，得到的截面可以是五边形

---Why did he get up so early in the morning?

--- He got up early in order that he could catch the early bus.

A．such that

B．so that

C．in order to

D．therefore