Which of the following statements is true about runway and taxiway surface lighting?

Runway and taxiway surface lighting is an essential component of airport operations, providing visibility for pilots during takeoff, landing, and taxiing, particularly in low-light conditions or adverse weather. The statement that it is not always available reflects the reality that lighting can be affected by various factors such as power outages, maintenance activities, or specific airport operations.

While many airports equip their runways and taxiways with lighting systems for safety, not all airports may have these systems in place, especially smaller or less trafficked facilities. Furthermore, lighting may not be operational at all times, such as during certain hours when the airport is closed or during maintenance. Therefore, the accurate understanding of surface lighting involves recognizing that while it is a crucial safety feature, its availability can fluctuate due to operational needs or technical issues.