What is the role of the signal mirror in survival signaling equipment?

The signal mirror is specifically designed to reflect sunlight, making it an effective tool for signaling in survival situations. When used properly, the mirror can project a bright flash of sunlight over long distances, which can attract the attention of rescuers or passing aircraft. The ability to direct this reflected light to specific targets allows for precise signaling, which can significantly increase a survivor's chances of being located and rescued.

The other options do not accurately describe the primary purpose of a signal mirror. While mirrors can reflect light, their main function is not to provide warmth or light in darkness, nor are they typically used for navigation by reflecting stars. Instead, the focus of a signal mirror is on its signaling capabilities through the reflection of sunlight.