Soaps do not work in hard water containing calcium and magnesium...

Options

1. A$Ca^{2 +}$ and $Mg^{2 +}$ ions form insoluble calcium and magnesium salts in the form of scum
2. B$Na^{+}$ and $K^{+}$ present in soap react with $Ca^{2 +}$ and $Mg^{+}$ and hinder cleansing process
3. Ca large amount of soap is to be used in presence of $Ca^{+}$ and $Mg^{+}$
4. Dscum formed by combination of $Na^{+}$ , $Ca^{2 +}$ and $Mg^{2 +}$ stick to the cloth and are not removed on agitation