What types of traffic control devices are commonly used in MOT?

The correct choice highlights the key traffic control devices utilized in Maintenance of Traffic (MOT) practices. Cones, barrels, and warning signs are specifically designed for use in work zones or road maintenance areas, making them essential tools for ensuring safety for both workers and drivers.

Cones are commonly used to delineate traffic lanes or to mark areas where vehicles should not enter. They are easily movable and can be quickly deployed to create visual barriers for drivers. Barrels, often seen in construction zones, serve a similar purpose but are larger and provide more substantial visibility and protection. Warning signs, which alert drivers to upcoming hazards or changes in traffic patterns, are crucial for conveying important information about road conditions.

In contrast, the other answer choices incorporate devices that may not specifically align with the primary objectives of MOT. Traffic lights and railroad signals are primarily intended for controlling traffic flow at intersections and over tracks, rather than in maintenance scenarios. Parking meters and streetlights are not directly involved with managing traffic in work zones. Lastly, while speed bumps and road closures serve traffic control purposes, they are not common devices for temporary traffic management used specifically during maintenance activities. Therefore, the focus on cones, barrels, and warning signs reflects the standard practices in MOT for ensuring safety and