The correct option is
D All of the above.
Any organism that cannot produce their own food is called as heterotrophs. They obtain its food and energy from plant or another animal. All animals, protozoans, fungi, and most bacteria are heterotrophs. Holozoic modes of nutrition is a method of heterotrophic nutrition that involves the ingestion of liquid or solid organic material, digestion, absorption and assimilation of it to utilize it. For example,
Amoeba. Saprophytes are the animals which feed on dead and decaying animals. For example, moulds, mushroom etc. Parasitic mode of nutrition is that in which organism feeds on a living organism (host). For example, leach, flatworm, plain worms etc.
Therefore, the correct answer is option D.