The correct option is A Protozoa
Protozoa
Phylum Protozoa is included in the kingdom Protista and includes eukaryotes, which are simplest and primitive of all animals.
There are four groups of protozoans namely amoeboid protozoans, ciliated protozoans, sporozoans and flagellated protozoans.
Amoeba is a type of amoeboid protozoan. Amoeba is a pathogenic protist. It moves and captures its prey by extending its pseudopodia.
Final answer
b. Protozoa