单选题On modern ships, centrifugal pump with a self-primer has replaced reciprocating pump as bilge pump because（）Acentrifugal pump is cheaper than reciprocating pumpBthe size of centrifugal pump with same capacity is smaller than that of reciprocating pumpCcentrifugal pump makes maintenance easier than reciprocating pump doesDall of the above
单选题
On modern ships, centrifugal pump with a self-primer has replaced reciprocating pump as bilge pump because（）
A
centrifugal pump is cheaper than reciprocating pump
B
the size of centrifugal pump with same capacity is smaller than that of reciprocating pump
C
centrifugal pump makes maintenance easier than reciprocating pump does
D
all of the above
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