$\left[{\mathrm{Co}}^{\mathrm{III}}(\mathrm{gly}{)}_3\right]$ is called inner-metallic complex or inner complex.

Because the ligands concurrently satisfy the coordination number and charge of the cation, $\left[{\mathrm{Co}}^{\mathrm{III}}(\mathrm{gly}{)}_3\right]$ is known as an inner-metallic complex or inner complex.

Some other examples of inner metallic complexes:

$\left[\mathrm{Cu}(\mathrm{big}{)}_2\right],\left[\mathrm{Cu}(\mathrm{gly}{)}_2\right],\left[\mathrm{Co}(\mathrm{acac}{)}_3\right]$

Hence correct option is A.