Kingdom Animalia is characterized by the following fundamental traits that encompass all the provided options:

Heterotrophic organisms: Animals cannot produce their own food through photosynthesis and must obtain nutrients by consuming other organic substances.

Eukaryotic organisms: Animal cells possess a clearly defined nucleus enclosed by a nuclear membrane, as well as other membrane-bound organelles.

Multicellular organisms: Animals are composed of multiple cells that are often specialized into tissues and organ systems.