What are apposition eyes?

• A. A type of single-lens eye
• B. Eyes that detect infrared radiation
• C. A type of compound eye with independently functioning ommatidia, best suited for bright light
• D. Eyes with fused ommatidia

Answer: (C)

Apposition eyes are a type of compound eye in which each ommatidium works independently because light is kept optically separate from its neighbors by pigment cells. That isolation lets every facet sample a distinct part of the scene, giving a mosaic image with good spatial resolution and color perception in bright light. This arrangement is typical of diurnal insects and is best suited for bright conditions, unlike systems where light from many facets is pooled to boost sensitivity in the dark. The other descriptions don’t fit because a single-lens eye lacks multiple ommatidia, infrared detection isn’t a defining feature of apposition eyes, and fused ommatidia would imply a different structural organization rather than independently functioning units.