In an octahedral crystal field,the $t_{2g}$ orbitals are:

Which of the following produces high crystal field splitting?

The $CFSE$ for $[CoCl_6]^{4-}$ complex is $18000 \ cm^{-1}$. The $\Delta_t$ for $[CoCl_4]^{2-}$ will be ........... $cm^{-1}$.

The crystal field theory is successful in explaining which of the following?
$I.$ Ligands as point charges;
$II.$ Formation and structures of complexes.
$III.$ Colour;
$IV.$ Magnetic properties;
$V.$ Covalent character of metal-ligand bonding.

Given below are two statements:
Statement $I$: Presence of a large number of unpaired electrons in transition metal atoms results in higher enthalpies of their atomisation.
Statement $II$: $d_{xy} = d_{xz} = d_{yz} < d_{x^2-y^2} = d_{z^2}$ and $d_{x^2-y^2} < d_{xy} = d_{xz} = d_{yz}$ are the $d$-orbital splittings in $[Fe(H_2O)_6]^{3+}$ and $[Ni(Cl)_4]^{2-}$ complex ions respectively.
In the light of the above statements, choose the correct answer from the options given below:

Among the following $Cr(III)$ complexes,which one will have the highest octahedral crystal field splitting?