Answer:
I do believe your answer is D: Most of Earth's mantle is always moving.
Hopefully this helped! :D
Online school can be easy or very hard depending on the person many people have a short attention span so when there given one assignment it would take then 2 hours or more because there distracted and that could cause them to get behind like me I have a short attention span and that’s causes many problems with my assignments.
Just took a quiz and I had to answer this question. I got a 95% and the correct answer is: Root.
Good luck!!
and
Happy studying!!