An ionic compound when dissolved in water has produced \[m\,{{A}^{n-}},n\,{{B}^{m-}}\] ions. What is the formula of the compound? [NDA]

• A. \[{{A}_{m}}{{B}_{n}}\]        
• B.        \[{{A}_{n}}{{B}_{m}}\]
• C. \[{{A}_{m}}{{B}_{m}}\]                  
• D.        \[{{A}_{n}}{{B}_{n}}\]