单选题During the fuel injection period, fuel pressure must exceed cylinder gas pressure to （）.Aensure penetration and distribution of the fuel in the combustion chamberBensure the needle valve is flushed clean during each injectionCprevent combustion gas blowback into the open needle valveDprevent reflected pressure waves when the needle valve closes
单选题
During the fuel injection period, fuel pressure must exceed cylinder gas pressure to （）.
A
ensure penetration and distribution of the fuel in the combustion chamber
B
ensure the needle valve is flushed clean during each injection
C
prevent combustion gas blowback into the open needle valve
D
prevent reflected pressure waves when the needle valve closes
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