Animals in the deep look very similar to the organism onthe right (they seem very prehistoric). This is because

Question

1)they come up to the surface during the day to feed and then go back down
2)the environment has been relatively stable for 100 million years so the organisms have not needed to adapt or change
3)they are able to do chemosynthesis
4)they need skin which can tear easily so it looks transluent

Answer 1

The statement that best explains why deep-sea animals look similar to prehistoric organisms is:

2) the environment has been relatively stable for 100 million years, so the organisms have not needed to adapt or change.

This stability in the deep-sea environment has led to a phenomenon known as evolutionary stasis, where certain traits remain unchanged over long periods because they are well-suited to the consistent conditions of their environment.