The diagram provided shows the carbon and nitrogen flow through a man-made mussel bed in the ocean. What evidence would support the law of conservation of mass for this ecosystem?

A. A The amount of carbon and nitrogen removed during harvest equals the amount seeded as biomass.
B. B Carbon and nitrogen enter and leave the ecosystem only through man-made processes.
C. C The mass of scavengers, decomposers, and feces equals the mass absorbed from phytoplankton and detritus.
D. D The total amount of carbon and nitrogen entering the ecosystem equals the total amount leaving the ecosystem.