C...the key is that they are photosynthetic...so they produce oxygen (like plants)!
Answer:
Either the cell wall or the cell membrane.
Explanation:
All cells have cell membranes which line the outside of the cell, and some cells have cell walls, which also line the outside of the cell. Since all cells have cell membranes I am inclined to believe that the correct answer would be cell membranes.
<span>Eukaryotic cells contain membrane-bound organelles, including a nucleus. Eukaryotes can be single-celled or multi-celled, such as you, me, plants, fungi, and insects. Bacteria are an example of prokaryotes. Prokaryotic cells do not contain a nucleus or any other membrane-bound organelle.</span>