单选题In an internal combustion engine, which of the devices listed will force the compression rings to seal the compression gases in the space above the piston?（）AUsed of bimetallic piston ringsBRing gap pre-tensioningCThermal increase in ring-end clearanceDGas pressure acting against the back of the ring
单选题
In an internal combustion engine, which of the devices listed will force the compression rings to seal the compression gases in the space above the piston?（）
A
Used of bimetallic piston rings
B
Ring gap pre-tensioning
C
Thermal increase in ring-end clearance
D
Gas pressure acting against the back of the ring
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