What can be considered a source of ignition?

Cigarette smoking is considered a source of ignition because it involves an open flame and hot embers that can easily ignite flammable materials. The act of lighting a cigarette generates enough heat to exceed the ignition temperature of various combustible substances, such as paper, fabric, or dry vegetation. This characteristic makes smoking a significant fire hazard, especially in environments where flammable materials are present.

In contrast, extreme weather, pollution, and flooding do not directly create ignition sources. While extreme weather can influence the spread of fires or create conditions conducive to them, it does not act as an ignition source itself. Pollution may reduce air quality or create environmental issues but does not initiate combustion. Flooding can damage infrastructure and potentially contribute to other fire hazards, but it does not inherently provide a source of ignition. Thus, cigarette smoking stands out as a clear source of ignition due to its direct involvement with fire and heat.