列车制动机进行简略试验时有何要求？

A. 主动锥齿轮
B. 从动锥齿轮
C. 行星
D. 半轴

A. increase ignition delay
B. affect fuel oil metering
C. affect engine performance at low speed
D. only disappear due to fuel oil abrasio

A. 正确
B. 错误