In which of the following ionization processes has the bond energy increased and the magnetic behaviour changed from paramagnetic to diamagnetic?

• A
  $NO \to NO^{+}$
• B
  $N_2 \to N_2^{+}$
• C
  $C_2 \to C_2^{+}$
• D
  $O_2 \to O_2^{+}$