Within the nucleus is a small subspace known as the nucleolus. It is not bound by a membrane, so it is not an organelle. This space forms near the part of DNA with instructions for making ribosomes, the molecules responsible for making proteins. ... The cell membrane is represented as the "factory walls." (Found on Khan Academy)
It’s b.
He grouped the types of creatures according to their similarities: animals with blood and animals without blood, animals that live on water and animals that live on land.
Response would be correct, as in response to environment.
