Which of the following signals does NOT indicate a fire condition?

The correct answer is that a supervisory signal does not indicate a fire condition. Supervisory signals are related to the overall status and integrity of the fire alarm system and its components. These signals may indicate issues such as maintenance needs, components being out of service, or troubles with equipment that are not directly related to an active fire situation.

In contrast, a fire alarm activation signal and smoke detection activation are specifically designed to indicate the presence of smoke or fire, prompting the necessary response to address a potential emergency. Similarly, a trouble signal generally indicates a fault within the fire alarm system, but it is not a direct signal of a fire condition either. However, supervisory signals stand apart as they focus on the operational readiness and any necessary ongoing maintenance, rather than responding to immediate hazards like a fire.