Two geared shafts \(A\) and \(B\) having moments of inertia \(I_{a}\) and \(I_{b}\) and angular acceleration \(\alpha_{a}\) and \(\alpha_{b}\) respectively are meshed together. \(B\) rotates at \(G\) times the speed of \(A\). If the gearing efficiency of the two shafts in \(\eta\), then in order to accelerate \(B\), the torque which must be applied to \(A\) will be

(a) \(I_{a} \alpha_{a}+G^{2} I_{b} \alpha / \eta\)

(b) \(G^{2} I_{a} \alpha_{a} \eta\)

(c) \(G^{2} I_{a} \alpha_{a} \eta\)

(d) \(G^{2} I_{b} \alpha_{b} / \eta\).