In each of four separate beakers (I, II, III, IV), X mL of $y \mathrm{M} \mathrm{Fe}_2 \mathrm{O}_3 x \mathrm{H}_2 \mathrm{O}$ colloidal solution is present. Equal volume and equal concentration of of KCl, $\mathrm{K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right], \mathrm{K}_3 \mathrm{PO}_4$ and $\mathrm{K}_2 \mathrm{SO}_4$ was added into I, II, III and IV respectively. The efficiency of precipitations in these beakers follows the order

• Correct answer
  A

  $\mathrm{II}>\mathrm{III}>\mathrm{IV}>\mathrm{I}$
• B

  $\mathrm{II}>\mathrm{III}>\mathrm{I}>\mathrm{IV}$
• C

  $\mathrm{I}>\mathrm{IV}>\mathrm{III}>\mathrm{II}$
• D

  $\text { III }>\text { IV }>\text { I }>\text { II }$

Hence, the correct answer is option: 'A'.