Temporary hardness is due to dissolved

• A

  ${\mathrm{HCO}}_3^{-}\text{of }{\mathrm{Ca}}^{2+},{\mathrm{Mg}}^{2+}\text{ and }{\mathrm{Na}}^{+}$

• B

  ${\mathrm{HCO}}_3^{-}\text{of }{\mathrm{Ca}}^{2+}\text{ and }{\mathrm{Mg}}^{2+}$

• C

  ${\mathrm{SO}}_4^{2-}\text{ and }{\mathrm{Cl}}^{-}\text{of }{\mathrm{Na}}^{+}\text{and }{\mathrm{K}}^{+}$

• D

  ${\mathrm{SO}}_4^{2-}\text{ and }{\mathrm{Cl}}^{-}\text{of }{\mathrm{Ca}}^{2+}\text{ and }{\mathrm{Mg}}^{2+}$