Answer: The answer is option B. Cell Walls
Explanation: Prokaryotic cells are much smaller than eukaryotic cells, have no nucleus, and lack organelles. All prokaryotic cells are encased by a cell wall. In eukaryotes, vertebrates don't have a cell wall but plants do.
D. the number of mates on the island
their appearance changes cause different birds breeding together can make an impact of how the bird looks
The process of metal refining is done for the purpose of fixing the metals impurities through the reduction process. On the other hand, problems are encountered in doing this process. Metal refining produces refined metals but the main downside of this process is the production of too much waste after.
I would assume that it would be A