An octahedral complex having molecular composition \( \mathrm{Co.5NH3.Cl.SO4} \) has two isomers A and B. The solution of A gives a white precipitate with \( \mathrm{AgNO3} \) solution and the solution of B gives white precipitate with \( \mathrm{BaCl2} \) solution. The type of isomerism exhibited by the complex is: