Which zone lies between the photic (well-lit) zone and the aphotic (no-light) zone, receiving limited light?

• A. Splash Zone
• B. Aphotic Zone
• C. Disphotic Zone
• D. Intertidal Zone

Answer: (C)

Light levels in the ocean create distinct depth zones: the photic zone is the well-lit layer where photosynthesis can occur, and the aphotic zone is dark with no usable light. Between these two lies the disphotic zone, the twilight layer where light is present but limited. In this zone, illumination is too faint for most photosynthesis, yet not completely absent, so organisms there are adapted to low-light conditions. The splash zone and intertidal zone are coastal features defined by exposure to air and tides, not depth-related light layers. The aphotic zone is the deeper, completely dark layer. So, the zone that lies between the photic and aphotic zones and receives limited light is the disphotic zone.