Which three-phase connection can be used in a transformer to introduce a phase difference of

Which three-phase connection can be used in a transformer to introduce a phase difference of 30o between its output and corresponding input line voltages 

(A) Star-Star (B) Star-Delta (C) Delta-Delta (D) Delta-Zigzag

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Answer :

Which three-phase connection can be used in a transformer to introduce a phase difference of 30o between its output and corresponding input line voltages 

(A) Star-Star (B) Star-Delta (C) Delta-Delta (D) Delta-Zigzag

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