Sulphate of divalent metal M exists in hydrated form. If 0.10 mol of metal sulphate combines with 9.0 g of water to form the hydrated salt then, the formula of metal sulphate will be

• A. \[\text{MS}{{\text{O}}_{\text{4}}}\text{.}{{\text{H}}_{\text{2}}}\text{O}\]
• B. \[{{\text{M}}_{\text{2}}}\text{S}{{\text{O}}_{\text{4}}}\text{.2}{{\text{H}}_{\text{2}}}\text{O}\]   
• C.  birds do not take care of their young ones
• D. \[\text{MS}{{\text{O}}_{\text{4}}}\text{.5}{{\text{H}}_{\text{2}}}\text{O}\]