tissue, cell, organ, organ system organ, cell, organ system, tissue cell, tissue, organ, organ system organ system, tissue, organ, cell
I gave my students this multiple choice question: The structures in the bodies of many organisms have levels of organization that help the body to carry out life processes. Which list correctly shows how these levels are organized from the simplest to the most complex?

Only one answer is correct among these 4 choices:
- tissue, cell, organ, organ system
- organ, cell, organ system, tissue
- cell, tissue, organ, organ system
- organ system, tissue, organ, cell

Could you tell me which one is correct?

cell, tissue, organ, organ system