Protista differs from monera in having: Cell wall, Autotrophic nutrition, Flagella, Nuclear membrane

All single-celled eukaryotes are placed under Protista. Being eukaryotes, the protistan cell body contains a well-defined nucleus with the nuclear membrane and other membrane-bound organelles. In contrast, monera is a group of organisms with a prokaryotic cell organisation that lacks a true nucleus. So, the correct answer is option 'D'.