Here's why:

* Eukaryotic cells are complex cells that have a membrane-bound nucleus containing their genetic material (DNA). This nucleus is a defining characteristic of eukaryotic cells.

* Prokaryotic cells, on the other hand, are simpler cells that lack a nucleus. Their DNA is located in a region called the nucleoid, which is not enclosed by a membrane.

So, any cell with a nucleus, whether it's a plant cell, animal cell, fungal cell, or protist cell, is considered a eukaryotic cell.