单选题The minimum speed an engine must attain before ignition can occur depends upon （）.Athe type and size of the engineBthe condition of the engineCambient temperatureDall of the above
单选题
The minimum speed an engine must attain before ignition can occur depends upon （）.
A
the type and size of the engine
B
the condition of the engine
C
ambient temperature
D
all of the above
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