Which one of the following statement is correct?

• A

  Ferric ions give a deep green precipitate on adding potassium ferrocyanide solution.

• B

  On boiling a solution having K⁺, Ca²⁺ and HCO₃^- ions, we get a precipitate of ${\mathrm{K}}_2\mathrm{Ca}{\left({\mathrm{CO}}_3\right)}_2$

• C

  Manganese salt give a violet borax test in reducing flame

• D

  From a mixed precipitate of AgCl and AgI, ammonia solution dissolves only AgCl