the plasma membrane of the eukaryotic host the nuclear membrane of the eukaryotic host the ribosomes of the engulfed prokaryotic cell the lysosomes of the engulfed prokaryotic cell
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: According to the endosymbiotic theory, double-membrane mitochondria originated as a result of some larger eukaryotic cells with flexible membranes engulfing smaller prokaryotic cells. Which of these explains where the outer layer of the double membrane of the mitochondria originated?
Possibilities:
- the plasma membrane of the eukaryotic host
- the nuclear membrane of the eukaryotic host
- the ribosomes of the engulfed prokaryotic cell
- the lysosomes of the engulfed prokaryotic cell

the plasma membrane of the eukaryotic host