Question on Magnetic Moment

The pair having the same magnetic moment is:

[Atomic Numbers: Cr = 24, Mn = 25, Fe = 26, Co = 27]

A) \([Cr(H_2O)_6)]^{2+} \ and \ [Fe(H_2O)_6]^{2+}\)

B) \([Mn(H_2O)_6)]^{2+} \ and \ [Cr(H_2O)_6]^{2+}\)

C) \([CoCl_4)]^{2-} \ and \ [Fe(H_2O)_6]^{2+}\)

A) \([Cr(H_2O)_6)]^{2+} \ and \ [CoCl_4]^{2-}\)