What action should be taken if you encounter a traffic signal that is not functioning?

When a traffic signal is not functioning, the action to take is to treat the intersection as if it were marked by a stop sign. This means that you must come to a complete stop, check for other vehicles and pedestrians, and proceed only when it is safe to do so. This approach ensures that drivers are cautious and attentive, helping to prevent accidents at intersections where signals are not operating.

The other options suggest reckless behaviors that could lead to dangerous situations. Speeding through the intersection could increase the risk of collisions, while waiting for the light to change is not appropriate since there is no functioning signal to respond to. Turning around might seem like a safe choice, but it doesn't address the immediate need to navigate the intersection safely. Treating the situation as a stop sign fosters safer driving practices and compliance with road rules in the absence of functioning traffic signals.