The right answer is A. Animalia.
Indeed, Animalia contains organisms that are multicellular, heterotrophic, eukaryotic, and does not have cell walls.
Protista is mainly unicellular organism, they are not considered as multicellular.
Plantae are an autotrophic organism, and does have cell walls.
Fungi are a heterotrophic and eukaryotic organism, but does have cell walls.
