What is the purpose of the runway end identifier lights?

The purpose of runway end identifier lights is to provide visual guidance for pilots, particularly during nighttime operations or in conditions of reduced visibility, such as fog or heavy rain. These lights are typically positioned at the ends of runways and emit a specific colored light pattern, which helps pilots easily identify the runway's location and alignment as they approach for landing or takeoff. This visual aid is crucial for ensuring safety, as it enhances situational awareness and assists in preventing runway incursions or accidents during critical phases of flight. The emphasis is on improving visibility in challenging conditions, thus making option B the most accurate choice.

In contrast, other options describe functions that do not align with the role of runway end identifier lights. Some may mistakenly associate these lights with signaling for takeoff clearance or marking designated parking areas, but those tasks are managed by different systems or visual aids. Additionally, while identifying the beginning of the runway is important, runway end identifier lights specifically highlight the end as opposed to the start, further distinguishing their function.