What indicates that the pull box will send a signal to the central station?

The correct answer highlights the significance of a white stripe on the pull box, indicating that it is designed to send a signal to the central station when activated. This feature is crucial for the operation of fire alarm systems, as it ensures that fire departments and emergency services are alerted quickly in case of a fire or emergency situation.

The presence of a white stripe serves as a visual cue, informing individuals that the box is connected to the central monitoring system. This understanding is essential for those involved in fire safety and emergency response, as it confirms that activating the box will initiate the appropriate alerting procedures.

In contrast, other markings or indicators, such as a blue stripe or a red light, do not have this specific purpose. They may represent different functions or statuses within the system, but they are not reliable indicators that the pull box will directly communicate with the central station.