What concept would best explain the perception of depth when viewing parallel lines that seem to converge?

The perception of depth when viewing parallel lines that seem to converge is best explained by linear perspective. This visual cue is based on the principle that parallel lines appear to meet as they extend into the distance, creating a sense of depth and spatial orientation. This phenomenon can be observed in various environments, such as roads, railway tracks, or corridors, where the sides of the path draw together in the distance, leading the viewer to infer depth.

In contrast, other concepts like texture gradient relate to how texture appears finer and less distinct with distance, relative size focuses on how perceived size changes based on distance from the observer, and interposition describes how one object obstructs another to indicate depth but does not specifically address the convergence of parallel lines. Thus, linear perspective distinctly captures the specific visual cue associated with the perception of converging lines in the context of depth perception.