Final answer:
Dustin's statement that both matter and energy cycle through an ecosystem is the most accurate, as energy flows through an ecosystem and is lost as heat, while matter is recirculated via biogeochemical cycles.
Step-by-step explanation:
Among the statements made by the four friends regarding how matter and energy move through an ecosystem, Dustin's statement aligns most closely with scientific understanding. Energy enters an ecosystem from external sources, primarily the sun, and flows through the ecosystem from producers to consumers in a one-way path, ultimately being lost as heat. Unlike energy, matter, such as water, carbon, and nitrogen, is recycled within the ecosystem through biogeochemical cycles. These cycles involve both living organisms and non-living matter, ensuring that matter is continually used and reused within the ecosystem.