A hydrogen atom makes a transition from $n=2$ to $n=1$ and emits a photon. This photon strikes a doubly ionized lithium atom $(z=3)$ in excited state and completely removes the orbiting electron. The least quantum number for the excited state of the ion for the process is :

Question

$\begin{array}{1 1}(1) 2 \\ (2) 3 \\ (3) 4 \\ (4) 5 \end{array} $