—How did you go home after the party last night?

—Well, there were no buses________we had to walk. [ ]

A. so as to  

B. in order to

C. so that  

D. in order that

当车辆（）时，混合动力系统能将车辆动能转化为电能，并储存在蓄电池中以备下次低速行驶时使用。

A、高速行驶

B、制动

C、低速行驶