Answer:
DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C). The order of these bases is what determines DNA's instructions, or genetic code.
Explanation:
 
        
             
        
        
        
Forward spatter is the blood that is ejected out of the exit wound,going the same direction as the bullet.back spatter is the blood ejected out of the entry wound,travelling against the line of fire and towards the shooter.
        
             
        
        
        
The answer should be B Convection