The correct option is A I.E2(N)>I.E2(O)
I.E2(Li)>I.E2(Be)
∵ An electron has to be removed from a stable 1s2 configuration in Li+ ion.
7[N]:1s22s22p3
8[O]:1s22s22p4
∴I.E1(O)<I.E1(N) because electron has to be removed from a stable half-filled configuration in N atom.
[N+]:1s22s22p2
[O+]:1s22s22p3
∴I.E2(O)>I.E2(N), Since O+ has a half-filled configuration, obviously it is more stable and has a greater ionisation energy than N+.