The correct answer is two liquids.

Key Points

• An emulsion
  • It can be defined as a colloid consisting of two or more non-homogenous types of liquids wherein one of the liquids contains the dispersion of the different forms of liquids.
  • Emulsions are the mixtures of two or more types of liquids where, one is such as droplets, of tiny or even ultramicroscopic size, which are distributed throughout each other. Hence, Option 3 is correct.
  • These are usually formed from the component of liquids either in natural form or, more often, using mechanisms such as agitation, which is provided that these fluids mixed have no kind of mutual solubility.
  • Emulsions are said to be stabilized by some agents forming films at the surface of droplets or those which impart to them a kind of mechanical stability.
  • The unstable form of emulsions eventually separates into two forms of liquid layers.
  • The stable emulsions are destroyed by destroying or by deactivating the emulsifying agent—for example by the addition of appropriate third-party substances or even by the process of freezing or by heating.
  • Some common emulsions are milk (where the dispersion of fat molecules or droplets in the aqueous solution) and also butter (which is the dispersion of droplets of particles of an aqueous solution in the fat).

• Theories of Emulsification
  • Since there are different processes and mechanisms (both chemical and physical) involved in the process of emulsification, there are several theories that accompany it.
• Surface Tension Theory: This theory states or describes emulsification as a process that occurs by the reduction of interfacial tension between two phases.
• Repulsion Theory: With this theory, we learn that the emulsifying agent produces a film over one phase which further leads to the formation of globules. These compounds tend to repel each other and the repulsive force that exists between them helps them to remain suspended in the dispersion medium.