The correct option is D Slime moulds
Slime moulds are saprophytic protists. They move their body along decaying twigs and leaves, engulfing organic material.
Chrysophytes, Euglenoids and Dinoflagellates are mostly photosynthetic.
When Euglenoids are deprived of sunlight, these behave like heterotrophs by predating on other smaller organisms.
Dinoflagellates may feed on other organisms as predators or parasites.