As you completed this assignment, the cells in your body were dividing and
the DNA in them was being copied, one
at a time.

DNA
Letter
Child
Mutation(used 2 times)

Plz help me

a) DNA

Explanation:

You can quickly take out c and d, because what does a child have to do it with it and mutation isn't going to be used twice.

Letter, I don't know how that could come into a DNA being copied.

Furthermore, the answer is DNA.

"one DNA at a time."

the reason the two sea urchins don't compete with each other for food, resources, etc. is because the urchins have adapted to the environment but they have also adapted to each other. this is most likely because the genes of the sea urchins.

the correct answer is:

a population changes in response to a change in the environment.