单选题Movement of the pump control rack in a fuel injection system using individual plunger-type pumps （）Achanges the position of the fuel inlet portsBchanges the length of the pump strokeCvaries the quantity of fuel deliveredDvaries the compression of the delivery valve spring
单选题
Movement of the pump control rack in a fuel injection system using individual plunger-type pumps （）
A
changes the position of the fuel inlet ports
B
changes the length of the pump stroke
C
varies the quantity of fuel delivered
D
varies the compression of the delivery valve spring
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