Lyophobic sols are not stable and are easily precipitated by adding electrolytes. Lyophilic colloids like gums, soaps, gelatin etc are added to prevent coagulation of lyophobic sol. The process is known as ‘protection' and the lyophilic colloids are termed as protective colloids.

Lyophilic colloids cover-up of the particles of the lyophobic colloid by the formation of a protective film or layer.

Thus both the options (i) and (ii) are correct.