What color lights are used to identify the edges of a taxiway?

Answer: D — Blue

Taxiway edge lights are used to delineate the edges of a taxiway from the surrounding areas, especially at night or in low-visibility conditions. The lights that mark the edges of taxiways are colored blue. This blue lighting helps pilots and ground vehicle operators easily identify the exact pathway they should follow, enhancing safety on the airfield. In contrast, the other colors represent different functionalities: red lights are used for runway boundaries and indicate that an obstruction or a stop point is ahead; green lights are typically employed for the centerline of the runway, guiding aircraft during approach and landing; and white lights serve to delineate runway edges. The use of blue lights along taxiways specifically ensures clear and distinguishable navigation, crucial for maintaining safe operations on the airfield.