What is a difference between prokaryotic and eukaryotic cells?

A.
Prokaryotic cells always have cell walls, but eukaryotic cells do not.
B.
Prokaryotic cells do not have a nucleus, but eukaryotic cells do.
C.
Eukaryotic cells do not have membrane-bound organelles, but prokaryotic cells do.
D.
Organisms with eukaryotic cells are always multicellular, but organisms with prokaryotic cells are not.