Which classification would include animals, plants, and most fungi based on cell structure?

The classification that includes animals, plants, and most fungi based on cell structure is multicellular. Multicellular organisms are composed of more than one cell, which allows for specialization and the formation of complex tissues and organs. This is a defining characteristic of animals, plants, and fungi, as they all exhibit differentiated cells that perform specific functions within the organism.

In contrast, the other classifications are less applicable to these groups. Monocellular refers to organisms that consist of a single cell and is more characteristic of many prokaryotes and some protists. Uninucleate describes cells that contain only one nucleus, which is common in many types of cells but does not encompass all multicellular organisms, as some can have multiple nuclei per cell. Multinucleate organisms have cells that contain multiple nuclei, which is not typical for animals, plants, or most fungi. Thus, multicellular is the most accurate classification for these complex life forms.