Which of the following is a sign of fire origin in a kitchen?

Open fires are a significant indicator of potential fire origin in a kitchen because they are directly associated with cooking processes. In a kitchen setting, open flames from gas burners, stovetops, or other cooking appliances can easily ignite flammable materials nearby. This makes it crucial to identify open fires as potential fire sources for safety and prevention measures.

By contrast, while gas tanks can pose a fire risk if not handled properly, they are not inherently indicative of the origin of a fire within a kitchen environment. Similarly, curtains and furniture may be affected by a fire, but they do not serve as direct signs of where the fire might have started, as they can catch fire from a variety of sources. Therefore, recognizing open fires provides a clear link to the cooking activity that often leads to fire incidents, making it an important aspect to consider when assessing fire safety in a kitchen.