Which of the following ligands can show linkage isomerism?

Linkage isomers are two or more coordination compounds with different donor atoms in at least one of the ligands (i.e., the connectivity between atoms is different). All of these ligands are capable of exhibiting linkage isomerism. CNS^- can connect from either the N or S side. NO₂^- can be attached from either the N or O side. CN can connect on either the C or N side.

${\mathrm{CNS}}^{-}$, ${\mathrm{NO}}_2^{-}$ and ${\mathrm{CN}}^{-}$are ambidentate ligands.

The correct answer is D.