一小船在静水中的速度为3 m/s，它在一条河宽150 m，水流速度为4 m/s的河流中渡河，则(　　)

A．小船渡河的时间可能少于50 s

B．小船不可能到达正对岸

C．小船以最短时间渡河时，它沿水流方向的位移大小为200 m

D．小船以最短位移渡河时，位移大小为150 m

She was so angry at        he was doing        she walked out, and closed the door heavily behind her.

A．what, that

B．that, what

C．that, that

D．what, what