In case of octahedral compex, if the `e_(g)` orbitals `(d_(x^(2) - y^(2)) " and " d_(z^(2)))` are asymmetricaaly filled, their degeneracy is destroyed and the ligands approaching along `+Z` and `-Z` directions experiences different amount of repulsions than the ligands approaching along the `+X, -X, +Y " and " -Y` directions. As a result, the symmetrical nature of such complexes is lost and either elongation or compression along Z-axis taken place. Answer the following three questions based on the above situation.
Which of the following is incorrect regarding `K_(4) [Cr F_(6)]` ?
A. It has two long and four short `Cr-F` bonds
B. It has four long and two short `Cr-F` bonds
C. spin only magnetic moment of the complex is approximately `4.9 Bm`
D. If `Cr` is replaced by `Cu`, similar types of deformation in the regular octahedral geometry are observed
