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单选题
When two AC generators are being paralleled, the breaker should be closed with the synchroscope pointer mating in the （）
A
slow direction, just before the 12 o'clock position
B
fast direction, just after the 12 o'clock position
C
fast direction, just before the 12 o'clock position
D
slow direction, just after the 12 o'clock position
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