单选题Why is the ring belt narrower in diameter than the skirt of a piston designed for a diesel engine?（）ATo allow for greater expansion due to higher operating temperatureBTo seal the cylinder against leakage of combustion gasesCTo provide an additional surface for oil coolingDTo provide an additional strength for the crown and lower structure
单选题
Why is the ring belt narrower in diameter than the skirt of a piston designed for a diesel engine?（）
A
To allow for greater expansion due to higher operating temperature
B
To seal the cylinder against leakage of combustion gases
C
To provide an additional surface for oil cooling
D
To provide an additional strength for the crown and lower structure
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