Which Pieces of Information Are Needed to Explain Why Ni(CN)₄²

Multiple Choice

Which pieces of information are needed to explain why Ni(CN) ₄^2 is diamagnetic?
I.It has six d electrons.
II.It has eight d electrons.
III.It is tetrahedral.
IV.It is square planar.
V.It is strong field.
VI.It is weak field.

A) II, IV, V
B) I, IV, V
C) II, III, V
D) II, III, VI
E) II, IV, VI