Addition of excess aqueous ammonia to a pink coloured aqueous solution of MCl 2 .6H 2 O(X) and NH 4 Cl gives an octahedral complex Y in the presence of air. In aqueous solution, complex Y behaves as 1 :3 electrolyte. The reaction of X with excess HC1 at room temperature results in the formation of a blue coloured complex Z. The calculated spin only magnetic moment of X and Z is 3.87 B.M., whereas it is zero for complex Y. Among the following options, which statement(s) is(are) correct?