The complexes $[Co{\left(N{H}_3\right)}_{5}N{O}_2 ]C{l}_2$ and $\left[Co{\left(N{H}_3\right)}_5\right(ONO\left)\right]C{l}_2$ are the examples of

The complexes $[Co{\left(N{H}_3\right)}_{5}N{O}_2 ]C{l}_2$ and $\left[Co{\left(N{H}_3\right)}_5\right(ONO\left)\right]C{l}_2$ are the examples of linkage isomers.

Two or more coordination compounds called linkage isomers have at least one ligand with a different donor atom than the others (i.e., the connectivity between atoms is different). Only a ligand that can form two (or more) distinct bonds with the metal atom may cause this kind of isomerism in a molecule.

Hence, option D is correct.