Give a method of removing the permanent hardness of water.

Given below are two statements: One is labelled as Assertion A and the other labelled as reason $\mathrm{R}$

Assertion $\mathrm{A}:$ During the boiling of water having temporary hardness, $\mathrm{Mg}{\left({\mathrm{HCO}}_3\right)}_2$ is converted to ${\mathrm{MgCO}}_3$

Reason $\mathrm{R}:$ The solubility product of $\mathrm{Mg}(\mathrm{OH}{)}_2$ is greater than that of ${\mathrm{MgCO}}_3$.

In the light of the above statements, choose the most appropriate answer from the options given below: