You discover a large, green, multicellular, autotrophic organism living on the bank of a creek. upon microscopic examination, you find that the cells contain nuclei and other membranous organelles. how would you classify this organism?

The answer is eukarya. While Eukarya, Archaea, and Eubacteria may share some similarities, the most distinctive feature of eukarya is the presence of a membrane-bound nucleus containing the cell's genetic information. This diverse group includes plants, animals, fungi, and protists (unicellular organisms).