【单选题】You are attempting to parallel two AC generators, and the synchroscope(同步器) pointer is revolving in the fast direction. This indicates that the frequency of the incoming machine is ______.
A.
higher than the bus frequency
B.
lower than the bus frequency
C.
the same as the bus frequency but out of phase with it
D.
the same as the bus frequency and the circuit breaker may be closed at any pointer position