The multiple choices for the questions are;
A) rRNA sequences
B) Metabolic type
C) Motility
D) Ecology
E) None of the above
The answer would be E none of the above.
Protists are eukaryotes, such that their cells have a nucleus membrane and other membrane-bound organelles. Most of them are single-celled. They differ in all other features, they are neither plants, nor fungi, nor animals.