Acidic ferric chloride solution on treatment with excess of potassium ferrocyanide gives a Prussian blue coloured colloidal species. It is :

• A
  $Fe_{4}[Fe(CN)_{6}]_{3}$
• B
  $K_{5}Fe[Fe(CN)_{6}]_{2}$
• C
  $HFe[Fe(CN)_{6}]$
• D
  $KFe[Fe(CN)_{6}]$