Question 134Navigation General

The correct answer is D) existing visibility conditions. The luminous range of a light takes into account the existing visibility conditions, which include factors such as atmospheric conditions, background lighting, and other environmental factors that can affect the distance at which the light can be seen. The luminous range is the maximum distance at which a light can be seen under the prevailing visibility conditions. The other answer choices are incorrect because they do not directly affect the luminous range of a light. The observer's height of eye (A) and the elevation of the light (B) can affect the geographic range of the light, but not the luminous range. Glare from background lighting (C) is a factor that can affect visibility, but it is encompassed by the "existing visibility conditions" that determine the luminous range.