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Which of the following is not a main characteristic that scientists focus on when determining which kingdom an organism belongs to

Cells tend to have a relatively small and uniform size. why aren’t cells larger?

The earth consists of a variety of different organisms. despite their diversity, however, some similarities on the structural and metabolic levels may be seen. these similarities can be attributed to a. similarities among organisms in their proteins and nucleic acids. b. the ability of organisms to readily adapt to sudden environmental changes. c. similarities in organisms' habitats and niches. d. the ability of all organisms to interbreed and produce new species.