In the context of energy flow through ecosystems, how does energy first enter a pond ecosystem?

• A. Energy enters through heat flowing upward from the sediment into the water column.
• B. Energy enters when primary consumers eat producers and transfer energy up the food web.
• C. Sunlight is captured by photosynthetic producers (such as algae and aquatic plants) and converted into chemical energy.
• D. Decomposers release energy into the pond by breaking down dead organic matter.

Answer: (C)