(N) None of the given option is correct. The molecular orbital configuration of the given molecules is H2=σ1s2σ1s0 (no anti-bonding electron) Li2=σ1s2σ*1s2σ2s2( two anti-bonding electrons) B2=σ1s2σ*1s2σ2s2σ*2s2{π2py1=π2pz1} ( 4 anti-bonding electrons) Though the bond order of all the species are same (B⋅O=1) but stability is different. This is due to difference in the presence of no. of anti-bonding electron. Higher the no. of anti-bonding electron lower is the stability hence the correct order is H2>Li2>B2