单选题If the flame from combustion in the cylinder of a four-stroke engine past the piston into the space below, the accumulation of flammable mixture would be ignited, thus resulting in （）.Athe crankcase explosionBlifting of the cylinder safety valveCa scavenge fireDopening of the manhole
单选题
If the flame from combustion in the cylinder of a four-stroke engine past the piston into the space below, the accumulation of flammable mixture would be ignited, thus resulting in （）.
A
the crankcase explosion
B
lifting of the cylinder safety valve
C
a scavenge fire
D
opening of the manhole
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