Which statement best describes eukaryotic cells?

• A. Larger and more complex with membrane-bound organelles and a nucleus
• B. Smaller and simpler with no nucleus
• C. DNA is circular
• D. Reproduce by binary fission

Answer: (A)

Eukaryotic cells are defined by having a nucleus enclosed by a nuclear membrane and a system of membrane-bound organelles that compartmentalize different cellular functions. This arrangement supports larger, more complex cells with organized DNA housed in linear chromosomes inside the nucleus and specialized compartments like mitochondria, endoplasmic reticulum, and Golgi apparatus that carry out distinct tasks. Because of this structure, eukaryotic cells can support more complex metabolism and regulation than prokaryotic cells.

The other descriptions describe typical prokaryotic features: lacking a true nucleus, having circular DNA in a nucleoid region, and commonly reproducing by binary fission. Those traits are not characteristic of eukaryotic cells, reinforcing why the statement about being larger and more complex with a nucleus and membrane-bound organelles is the best fit.