Final answer:
The statement true of eukaryotes but not of prokaryotes is that eukaryotes have a nucleus. Eukaryotic cells contain a true, membrane-bound nucleus and other specialized membrane-bound organelles for efficient cell functioning.
Step-by-step explanation:
The correct answer to the question is b) "Eukaryotes have a nucleus." Unlike prokaryotic cells, eukaryotic cells possess a membrane-bound nucleus where their genetic material is stored. This nucleus is often referred to as a "true nucleus" because it is enclosed within a membrane.
Moreover, eukaryotic cells feature membrane-bound organelles such as the endoplasmic reticulum, Golgi apparatus, chloroplasts, and mitochondria, which provide specialized functions and enable greater compartmentalization. This compartmentalization allows for regulated gene expression and efficient cellular operations, unlike in prokaryotic cells where such organelles are absent.
To clarify the other options, eukaryotes do not lack membrane-bound organelles, they are generally larger in size compared to prokaryotes, and their reproduction is not limited to binary fission as is typically found in prokaryotic cells.