Incorrect Ribosome Uniformity in Plant Cells Steps:

• Evaluate DNA packaging: prokaryotes use histone-like proteins, eukaryotes use true histones—both organize DNA.
• Assess organelle presence: prokaryotes lack ER, while eukaryotic plant cells have rough and smooth ER.
• Compare cell walls: prokaryotes use peptidoglycan for rigidity, plant cells use cellulose for structure.
• Examine ribosomes: prokaryotes have uniform 70S (~18-20 nm), but plant cells have mixed 80S (~25 nm) and 70S (~20 nm) types.

Why D is correct:

• Eukaryotic plant cells have 70S ribosomes in mitochondria and chloroplasts plus 80S in cytosol, violating the "all approximately 22 nm" claim per organelle definition.

Why the others are wrong:

• A: Prokaryotic DNA associates with histone-like proteins (e.g., HU), similar to eukaryotic histone association.
• B: Prokaryotes lack endoplasmic reticulum as they have no membrane-bound organelles.
• C: Prokaryotic walls contain peptidoglycan; plant eukaryotic walls contain cellulose.

Final answer: D