单选题Possible phase relationships between voltage and current in an alternating current circuit include which of the following conditions?（）ACurrent and voltage may be in phaseBCurrent may lead the voltageCCurrent may lag the voltageDAll of the above
单选题
Possible phase relationships between voltage and current in an alternating current circuit include which of the following conditions?（）
A
Current and voltage may be in phase
B
Current may lead the voltage
C
Current may lag the voltage
D
All of the above
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