The correct option is D Silver solution
Colloidal solution in which the particles of the dispersed phase have a great affinity for the dispersion medium is called lyophilic colloids.
These type of colloids can be formed easily whereas lyophobic colloids are formed with little difficulty by special methods.
Lyophilic colloids are reversible in nature.
If the dispersion medium is separated from the dispersed phase and sol can be reconstituted by simply remixing with the dispersion medium.
Hence, they are known as reversible sols.
Examples of lyophilic colloids:
Glue, gelatin, starch, proteins, egg albumin, rubber, etc.
Silver solution on the other hand is an example of lyophobic colloids.