单选题In order to keep excess oil from the intake ports in two-stroke/cycle diesel engines, （）Awide compression rings are usedBoil rings are located above the pistonCchromium plating is used on all piston ringsDoil rings are located near the bottom of the piston skirt
单选题
In order to keep excess oil from the intake ports in two-stroke/cycle diesel engines, （）
A
wide compression rings are used
B
oil rings are located above the piston
C
chromium plating is used on all piston rings
D
oil rings are located near the bottom of the piston skirt
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