Stability of the species $Li_2 , Li^{-}_2$ and $Li^{+}_{2}$ increases in the order of

Question

$\begin{array}{1 1} (1) Li_2 < Li_2^{+} < Li_2^{-} \\ (2) Li_2{-}_2 < Li_2^{+} < Li_2 \\ (3) Li_2 < Li_2^{-} < Li_2^{+} \\(4)Li_2^{-} < Li_2 < Li_2^{+} \end {array}$