Because the sun adds light to the clear bubble
        
             
        
        
        
A dam is a structure built across a stream or river to hold water back. Dams can be used to store water, control flooding, and generate electricity.
        
                    
             
        
        
        
It differs from DNA chemically in two respects: (1) the nucleotides in RNAare ribonucleotides—that is, they contain the sugar ribose (hence the name ribonucleic acid) rather than deoxyribose; (2) although, like DNA,RNA contains the bases adenine (A), guanine (G), and cytosine (C), it contains the base uracil (U) .
        
             
        
        
        
I believe the answer is B. Hope I help! Sorry if not. ):)