The alarm system for an engine order telegraph uses small selsyn motors attached to the indicators. The alarm sounds when the rotors are _____________.  A. in synchronous position, no current is flowing, and the relays are open B. in synchronous position, no current is flowing, and the relays are closed C. not synchronized, current is flowing, and the relays are open D. not synchronized, current is flowing, and the relays are closed

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Answer :

Answer: D

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