Why is CO2 preferred in certain fire suppression scenarios?

In fire suppression scenarios, carbon dioxide (CO2) is preferred primarily because it displaces the oxygen available for combustion. Fires require three components to exist—fuel, heat, and oxygen—often referred to as the fire triangle. When CO2 is introduced into a fire environment, it reduces the concentration of oxygen below the level needed to support combustion, effectively suffocating the fire without leaving any residue, which is an added advantage in certain situations, especially in environments like data centers or server rooms where equipment can be damaged by water or foam agents.

The action of CO2 is particularly effective in enclosed spaces, where it can be concentrated to lower oxygen levels rapidly. Its effectiveness in smothering flames makes it a valuable tool for firefighters and safety professionals. The other options provided, such as cooling the surrounding area or enhancing visibility, do not reflect the primary mechanism by which CO2 suppresses fires. Additionally, while creating a smokescreen may obscure visibility, it does not contribute to the suppression of flames in the way that oxygen displacement does. Thus, CO2's unique property of displacing oxygen directly addresses the fire triangle's requirement for oxygen, making it the correct answer in this context.