Among the structures given below,which one is not a correct resonance structure of $N_3^-$?

• A
  $N \equiv N - N^{2-}$
• B
  $\overline{N} = N^{+} = \overline{N}$
• C
  The structure with a bent geometry: $N$ (with lone pair and negative charge) bonded to a central $N^{+}$ (double bonded to both terminal $N$ atoms).
• D
  None of the above