Which statement is TRUE about fire fighting foam?

A
The air bubbles in foam act as an insulator in fighting a class C fire.
B
The effectiveness of foam in forming a blanket over a burning liquid increases as the temperature of the liquid increases.
C
Foam can be used to control gases escaping from compressed gas cylinders.
D
Foam sets up a vapor barrier over a flammable liquid preventing flammable gases from rising.
E