单选题The four-stroke cycle is so called because it takes （） to complete the processes needed to convert the energy in the fuel into work.Atwo strokes of the pistonBfour strokes of the pistonCone revolution of the crankshaftDfour revolutions of the crankshaft
单选题
The four-stroke cycle is so called because it takes （） to complete the processes needed to convert the energy in the fuel into work.
A
two strokes of the piston
B
four strokes of the piston
C
one revolution of the crankshaft
D
four revolutions of the crankshaft
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