What does a flashing green light indicate on the ground?

A flashing green light on the ground indicates that the aircraft is cleared for taxi. This signal is used by airport ground control personnel to communicate to pilots that it is safe to begin moving on the taxiways. Understanding this signal is crucial for maintaining safe and orderly movement on the airport surface, particularly in busy environments or when visibility is limited.

While the other options refer to important communications, they relate to different phases of flight and operational contexts. For instance, a steady green light would indicate a clearance for takeoff or landing, while other signals address runway use or returning to a starting point. Hence, recognizing that a flashing green light specifically denotes "cleared for taxi" is key for pilots to ensure they are following proper ground procedures.