Emulsions are liquid-liquid colloidal systems, i.e., the dispersion of finely divided droplets in another liquid.
If a mixture of two immiscible or partially miscible liquids is shaken, a coarse dispersion of one liquid in the other is obtained which is called emulsion.
Emulsions of oil in water are unstable and sometimes they separate into two layers on standing.
The emulsifying agent forms an interfacial film between suspended particles and the medium, which stabilises the Emulsion.
Examples of emulsifying agents are proteins, gums, natural and synthetic soaps,heavy metal salts of fatty acids, long chain alcohols, lampblack.
Here, electrolyte is not an emulsifying agent and hence is the correct option.