单选题Which of the following pumps are self-priming, and can deal with liquid from a level below the pump? （） (1) reciprocating (2) rotary (3) centrifugalA（1）onlyB（1）and（2）C（1），（2）and（3）D（2）and（3）
单选题
Which of the following pumps are self-priming, and can deal with liquid from a level below the pump? （） (1) reciprocating (2) rotary (3) centrifugal
A
（1）only
B
（1）and（2）
C
（1），（2）and（3）
D
（2）and（3）
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