Which principle of Figure-ground is involved in harder visibility due to blending the figure with the background?

The principle of Figure-ground that is involved in harder visibility due to blending the figure with the background is camouflage. This principle refers to the phenomenon where an object (the figure) becomes difficult to distinguish from its surroundings (the ground) because the colors, patterns, or textures are similar or match the background closely. This blending can lead to confusion in perception, making it challenging for individuals to identify the figure against the ground. Camouflage is commonly observed in nature, where an animal's coloration or pattern helps it remain unnoticed among its environment, illustrating how perception is affected by the relationship between the figure and the background.

In contrast, the other principles, such as proximity, continuity, and closure, relate to how we perceive and organize visual elements based on their spatial relationships, linear paths, and completion of shapes, rather than the blending effect that makes visibility more difficult.