The main difference between prokaryotic and eukaryotic cells is that
a. prokaryotic cells are always much larger.
b. prokaryotic cells do not have a plasma membrane.
c. eukaryotic cells have a smaller cell nucleus.
d. eukaryotic cells have a more complex cellular organization.

The correct answer is option D.

Explanation:

Eukaryotic cells are the complex cellular organization with several specialized cellular organelles and a true nucleus in the center of the cell with genetic material present in it. The eukaryotic cell is more like a building with complex structures and parts with different functions specified with it.

In contrast, prokaryotic cells are more like a stadium with a simple organization without membrane-bound cell organelles and these cells lack true nucleus in them and genetic material also present in the cytoplasm.

Thus, the correct answer is option D.

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