What term describes the depth cue from two eyes enabling three-dimensional perception?

• A. Stereopsis
• B. Fusion
• C. Monocular cues
• D. Accommodation

Answer: (A)

Depth perception from two eyes is stereopsis. This binocular depth cue comes from the small differences between the images each eye sees because the eyes are spaced apart. The brain compares these disparities and constructs a single, three-dimensional scene, giving you accurate depth and distance information. Fusion refers to the merging of the two retinal images into one view, which happens as part of using both eyes but isn’t the depth cue itself. Monocular cues provide depth with one eye (like perspective or shading), not from both eyes. Accommodation is about the eye’s lens changing focus and is a monocular cue, not the binocular depth cue described here.