In open-water marine ecosystems, the ________ occupy the same trophic level as the giant sequoias (redwoods) in the forests of California

A) fast-swimming, fish-eating tuna
B) giant, squid-eating whales
C) microscopic bacteria that decompose all the other organisms once they have died
D)  microscopic, single-celled algae (protists) called phytoplankton (“plant-like drifters”)
E) tiny, multicellular zooplankton (“animal drifters”) that feed on phytoplankton.