A vessel engaged in replenishment or transferring persons，provisions or cargo while under way can be regarded as（）.

A.a vessel restricted in her ability to maneuver

B.a vessel engaged in laying，serving or picking up a navigation mark，submarine cable or pipeline

C.a vessel not under command

D.a power-driven vessel

以下不属于汽车底盘测功试验台的功能的是（）

A.检验汽车加速性能

B.检测汽车制动性能

C.检验汽车滑行性能

D.校验车速表