Answer: Nucleotides
Explanation: 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).
 
        
                    
             
        
        
        
I believe it is natural. If so. Here's your answer.
Biotic natural resources also include fossil fuels such as coal and petroleum which are formed from organic matter that has decayed. Abiotic: these resources come from non-living and non-organic material. Examples of these resources include land, fresh water, air, and heavy metals (gold, iron, copper, silver, etc.). 
If not. Let me know. 
 
        
                    
             
        
        
        
The right option is b. mutualism
Mutualism is a relationship
between two organisms of different species in which both organisms benefit from
the relationship. From the question given above, both the oxpeckers and the
zebras benefits from the relationship. This type of relationship describes
mutualism.
 
        
             
        
        
        
<span>Well for starters, technology could prevent diseases. 
Hoped I helped!
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