the lysosome of an engulfed prokaryotic cell the chloroplast of an engulfed prokaryotic cell the cell membrane of an eukaryotic host cell the chloroplast of an eukaryotic host cell
I gave my students this multiple choice question: According to the endosymbiotic theory, the outer membrane of the chloroplast originated from which organelle?

Only one answer is correct among these 4 choices:
- the lysosome of an engulfed prokaryotic cell
- the chloroplast of an engulfed prokaryotic cell
- the cell membrane of an eukaryotic host cell
- the chloroplast of an eukaryotic host cell

Could you tell me which one is correct?

the cell membrane of an eukaryotic host cell