Answer:
The incorrect statement is that protists are all unicellular.
Step-by-step explanation:
Not all the protists are unicellular, there are some species of protists, which are multicellular too. The kingdom Protista comprises unicellular as well as eukaryotic species. The kingdom Protista is very diverse and comprises almost all the kinds of species beginning from unicellular species to multicellular, non-photosynthetic to photosynthetic and others. Some of the unicellular protists are paramecium, euglena, amoeba, while some of the multicellular protists are slime molds, kelp, and red algae.