单选题An increase in the fuel injection pump discharge pressure can be caused by a/an （）Aleaking delivery valveBexcessive bearing end playCplugged injector spray holeDincreased plunger stroke
单选题
An increase in the fuel injection pump discharge pressure can be caused by a/an （）
A
leaking delivery valve
B
excessive bearing end play
C
plugged injector spray hole
D
increased plunger stroke
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