Arrange the following complexes in increasing order of their magnetic moment

(A) $[Cr(H_2O)_6]^{3+}$
(B) $[Co(NH_3)_6]^{3+}$
(C) $[FeCl_6]^{4-}$
(D) $[Mn(CN)_6]^{3-}$

Choose the correct answer from the options given below:

(B), (D), (A), (C)

The correct answer is Option (2) → (B), (D), (A), (C)

Detailed calculation of unpaired electrons and magnetic moment:

Increasing order of magnetic moment:

0 < 2.83 < 3.87 < 4.90 B.M.

So: (B) < (D) < (A) < (C)