Answer;
D. high energy content of phytoplankton
Explanation;
-Tertiary consumers can be more abundant than primary producers, but primary producers will always make the highest quality energy.
-Certain aquatic ecosystems have inverted biomass pyramids: producers (phytoplankton) are consumed so quickly that they are outweighed by primary consumers (zooplankton).
-The biomass of zooplankton is greater than phytoplankton (the producer ) because of their small size and low weight . The predatory fish is much larger than zooplankton.