Consider an ideal single-phase 2-winding transformer of turns ratio \(N_{1} / N_{2}=a\). If it is converted to an autotransformer arrangement with a transformation ratio of \(V_{H} / V_{X}=1+a\), (the autotransformer rating) two-winding transformer rating) would then be

(a) \(1+a\)

(b) \(1+\frac{1}{a}\)

(c) \(a\)