Which type of foam is known for its ability to resist the effects of alcohol?

Alcohol-resistant foam is specifically formulated to combat fires involving polar solvents, such as alcohols and other flammable liquids. This type of foam has unique properties that enable it to form a stable film over the surface of these liquids, effectively preventing the vaporization of flammable vapors and minimizing the risk of re-ignition.

In contrast, regular Class A foam is designed to enhance the ability of water to extinguish ordinary combustible materials, and regular Class B foam is suitable for non-polar liquids but lacks the specialized formulation that allows it to effectively handle polar solvents. Water-enhanced foam, while beneficial in certain contexts, similarly does not target the unique challenges posed by alcohol fires. Thus, alcohol-resistant foam is the only option that effectively addresses the hazards associated with alcohol fires, making it the correct choice.