问题详情

When good and steady service conditions have been achieved, the running surfaces of the piston rings and cylinder liner will be_____In addition, the rings will move freely in the grooves and also be well oiled intact, and not unduly worn.

A.hazy light

B.hazy light brown

C.hazy light blue

D.hazy light grey

请帮忙给出正确答案和分析，谢谢！