How does Class A foam assist in fire suppression?

Class A foam assists in fire suppression primarily by lowering the surface tension of water. This reduction in surface tension allows the water to spread more easily and penetrate combustible materials more effectively, thereby cooling the material down and soaking it. By enhancing the water's ability to wet surfaces, Class A foam ensures better coverage and increased effectiveness in extinguishing fires, particularly in scenarios involving solid fuels like wood, paper, and textiles. This property makes it a valuable tool for firefighters, as it improves the overall efficiency of water used in combating fires.

While the other options suggest various effects a substance might have, they do not accurately describe the primary function of Class A foam in fire suppression.