In the preparation of potash alum, from saturated solutions of ${\text{K}}_{\text{2}}{\text{SO}}_{\text{4}}{\text{ and Al}}_{\text{2}}{{\text{(SO}}_{\text{4}}\text{)}}_{\text{3}}$,dilute sulphuric acid is added to ${\text{Al}}_{\text{2}}{{\text{(SO}}_{\text{4}}\text{)}}_{\text{3}}$crystals while preparing its saturated solution. This is due to

• A

  prevent hydrolysis of ${\text{Al}}_{\text{2}}{{\text{(SO}}_{\text{4}}\text{)}}_{\text{3}}$

• B

  make the solution more saturated

• C

  speed up crystallization

• D

  increase the solubility of ${\text{Al}}_{\text{2}}{{\text{(SO}}_{\text{4}}\text{)}}_{\text{3}}$