What is the primary difference between the kingdoms Protista and Plantae?

A. Protists are unicellular, while plants are multicellular
B. Protists perform photosynthesis, while plants do not
C. Protists have cell walls made of cellulose, while plants do not
D. Protists are autotrophic, while plants are heterotrophic

Answer: Protists are unicellular, while plants are multicellular


Additional Information: Most protists are unicellular organisms, while plants are multicellular and perform photosynthesis.