Which statement best contrasts the light requirements and productivity constraints of coral reefs versus kelp forests?

• A. Coral reefs depend on strong light for symbiotic algae and high productivity in clear waters; kelp forests require clear water for light and can be constrained by turbidity and nutrient shifts.
• B. Coral reefs thrive in turbid waters while kelp forests require deep, dark waters.
• C. Coral reefs do not depend on light, whereas kelp forests require extremely high nutrient concentrations.
• D. Coral reefs and kelp forests have identical light requirements and productivity patterns.

Answer: (A)