Answer:
B. It acts to hold the vinegar and oil together in a colloid.
Explanation:
Egg yolk contains lecithoprotein and yolk is an emulsion. An emulsion is a temporary stable mixture of immiscible fluids. It functions as an effective and efficient emulsifying agent. It emulsifies by reducing surface tension and reduces the force which is needed to make the droplets that comprise an emulsion. Thus, egg yolk holds or stabilizes oil and vinegar together.