the following what anyways it means the formation of a number of things into a cluster. i hope it helped
 
        
             
        
        
        
The cell theory of course had an important impact on later scientific discoveries as many different hypothesis and scientific discoveries were derived and concluded with the help of basics from this theory.
        
             
        
        
        
B. comet 
comets only have tails because the sun is shining its light on the ice and dust behind the comet
        
             
        
        
        
The controlled variable is what stays the same . So it’s C . They are given different amounts but the same food.