Answer D. Because the DNA is different
The answer is a because you're not focusing on numbers (quantities), you're simply observing something
Natural selection allows nature to chose which species survives. Only the fittest get to pass on their genes. And by fittest i mean the ones that are better adapted to the environment.<span />
They do not have a cell wall because only plant cells have that. The plant cells have that to help with the process for creating the green color. The animal cells, instead, they have a cell membrane.
The borders (coastlines) of the continents underwent a number of changes
since the split. Often, chunks of land were washed away with water,
slowly or in bigger portions. The coast was generally "smoothed" by the
ocean currents too, and in some places more land was added with the
material that the ocean currents brought.
Then, the tectonic plates continue to move, so this adds to the changes of the shape of the continents.
