<span>C. Cells, Tissues, Organs, Organ Systems
The answer is C. Cells are the fundamental unit of life. Without them, life would not possibly exist. Well that is according to the cell theory, which states that cells are the basic unit of life, cells came from pre-existing cells and cells make up living organisms.
</span>
The answer is that <span>all
veins carry blood back to the heart, except for the pulmonary vein. the
vena cava empty into the right side of the heart, so they technically
bring blood to the
</span>main atrium.
They <span>Cytoskeleton aids in cell division but its not important.</span>
Answer:
a process where living organisms develop and change during the history of earth to help them survive