An electrician is installing a new 480/277V, 3-phase separately derived system from a transformer inside a building. According to NEC 250.30(A), which of the following must be used as the grounding electrode for this new system?
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A
The nearest available metal water pipe
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B
Two new 8-foot ground rods driven 6 feet apart
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C
The existing building or structure grounding electrode system
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D
An isolated, dedicated ground plate buried near the transformer