The correct option is D None of the above.
A) Due to the noble gas configuration of Li+ (1s2), it has higher ionization energy than Be+.
B) Due to the half filled configuration of O+ (2s2 2p3), it has higher ionization energy than N+.
C) Due to the poor shielding of 3d electrons, the ionization energy of Ga is greater than Al.
All the statements are correct.