单选题An individual injection pump is designed for variable beginning and constant ending of injectionFor diesel engines operating at constant speeds, the start of injection will（）Aadvance as the load increasesBretard as the load increaseCremain unchanged regardlessDalways occur at top dead center
单选题
An individual injection pump is designed for variable beginning and constant ending of injectionFor diesel engines operating at constant speeds, the start of injection will（）
A
advance as the load increases
B
retard as the load increase
C
remain unchanged regardless
D
always occur at top dead center
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解析：
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