The answer would be: <span>A. Mitochondrial DNA is beneficial in both of these cases
</span>
Mitochondrial DNA or mtDNA is DNA that found in the mitochondrial. Mitochondrial DNA only inherited from mother, so it's relatively unchanged than nuclear DNA that mixed from father and mother. 
Mitochondrial DNA has higher mutation rate in animals because it doesn't have repair mechanism like nuclear DNA. These mutations can be used as a clue for how close the relation of an organism to others.
This makes analyzing the ancestral relationship of organisms that closely or distantly related easier.
        
             
        
        
        
This is a cellular respiration question, related to biology.
Some processes in our bodies require the use oxygen, others do not.
In this case, the conversion of pyruvic acid to acetyl co-enzyme A and the production of water in the electron transport chain do require oxygen. 
If oxygen was not present for pyruvate, it would turn into lactic acid via fermentation. Water in the ETC is formed in the process when NADH and FADH2 are converted to molecular oxygen due to the electron transporters. The protons are then pumped and oxygen is reduced to form H2O. 
 
        
                    
             
        
        
        
The subatomic parts of an atom are the protons, neutrons, and electrons. Protons have a positive charge, neutrons have a neutral(no) charge, and electrons have a negative charge.
 
        
             
        
        
        
Your answer is true lol  hope that helped