单选题The purpose of the commutator and brushes on a DC generator is to（）Achange AC to DCcurrentBchange DC to AC currentCneutralize a armature reactionDcarry current to the outside circuit
单选题
The purpose of the commutator and brushes on a DC generator is to（）
A
change AC to DCcurrent
B
change DC to AC current
C
neutralize a armature reaction
D
carry current to the outside circuit
参考解析
解析：
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