New York Driver License (DMV) Written Practice Test

The correct answer is that traffic lights may not change at all when they are malfunctioning. This indicates a serious issue, as traffic signals are designed to operate in a predictable cycle, controlling the flow of traffic by changing from red to green and then to yellow.

When a traffic signal fails to change, it can create confusion for drivers, leading to potential accidents. This scenario often requires drivers to treat the intersection as a four-way stop if there's no police officer directing traffic, enhancing safety until the situation is resolved.

The other scenarios provided may indicate different types of issues with traffic signals. For instance, flashing yellow lights suggest that drivers should slow down and proceed with caution, rather than indicating a complete malfunction. All lights remaining red could mean a temporary halt due to construction or another event but does not specifically point to malfunction. Flickering between green and red generally signifies a malfunction but is less common than a traffic light completely failing to change, which can lead to more hazardous conditions. Understanding these nuances is vital for safe driving and navigating intersections effectively.