单选题The advantage of a centrifugal pump as compared with a reciprocating pump is that （）.Adischarge is continuousBit has no internal valvesCupon accidental closing of discharge valve, excessive pressure will not build upDall of the above are true
单选题
The advantage of a centrifugal pump as compared with a reciprocating pump is that （）.
A
discharge is continuous
B
it has no internal valves
C
upon accidental closing of discharge valve, excessive pressure will not build up
D
all of the above are true
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