Which of the following is NOT a characteristic of eukaryotic cells?

The absence of a plasma membrane is indeed the correct choice for what is NOT a characteristic of eukaryotic cells. Eukaryotic cells are defined by their complexity, which includes the presence of a plasma membrane that encases the cell and regulates the movement of substances in and out of the cell. This membrane is essential for maintaining the cell's internal environment, enabling communication with the external environment and allowing it to participate in critical processes such as nutrient uptake and waste removal.

In addition to the plasma membrane, eukaryotic cells contain a nucleus, which houses the cell's genetic material. They also feature multiple organelles, such as mitochondria, endoplasmic reticulum, and Golgi apparatus, each with specialized functions. This complexity is a hallmark of eukaryotic cells, distinguishing them from prokaryotic cells, which are generally simpler and lack a nucleus and membrane-bound organelles. Thus, the presence of a plasma membrane is a fundamental characteristic of eukaryotic cells, and the claim of their lack is inaccurate.