A is the most sensible answer
        
                    
             
        
        
        
Answer:
The cell pictured in the diagram is a plant cell because there is are chloroplasts. Chloroplasts are located in plant cells and not in animal cells. Chloroplasts are where photosynthesis occurs, and photosynthesis does not occur in animals. 
 
        
             
        
        
        
Answer:
By doing more research.
Explanation:
The cell theory change with the passage of time by doing more research about the cell. The final modification of the cell theory done by Rudolf Virchow in 1855 on the basis of his new research and findings about the cells.    With the passage of time, modification occurs in microscope which enable the scientists to find different parts, organelles and features of cell on the basis of which scientists modify cell theory with the passage of time.
 
        
             
        
        
        
the ball would represent the nucleus of the eukaryotic cell!
        
             
        
        
        
It is a substance that takes part in and undergoes change during a reaction