Answer: Option B. 
Explanation:
The first experiment of the passage shows that treatment with TGFBR1 and TGFBR2 antagonists led to lower levels of epithelial cell production. For this conclusion to be strongly valid, we want to show a positive correlation between TGFBR activity and epithelial proliferation. 
 
        
             
        
        
        
All living things are made up of cells. All non-living things are not.
A dill pickle is technically "living" since it was once growing as a plant. Therefore, the dill pickle has cells.
However, the rest of the items do not, as they are non-living things.
        
             
        
        
        
Allowing the body to "fix" itself
It wants to be healthy and it works to reach it.
example: shiver when cold. sweat when hot
        
             
        
        
        
Answer:
Increasing the size of the cube-shaped cell increases the volume. However, the surface area-to-volume ratio decreases. This means that the simple diffusion would take more time distribute nutrients across the cell (and even in the eliminate waste). It would need bulk transport such as vesicle transport, otherwise cell activities would slow down. 
 
        
             
        
        
        
B.produce antibodies when triggered by antigens