Antibiotic resistance 
Antibiotic resistance occurs when bacteria change in some way that reduces or eliminates the effectiveness of drugs, chemicals, or other agents designed to cure or prevent infections. The bacteria survive and continue to multiply causing more harm.
        
             
        
        
        
Answer:
Net membrane potential is equal to the difference of positive charge and negative charge existing at the inner and outer side of the cell respectively. Since outer negative charge is higher in concentration, the net membrane potential is negative
Explanation:
The cell membrane potential defined as the net difference of ion concentration existing at the inner and outer side of a cell membrane at nay instance.  
When the cell is at the resting potential, the positive potassium ion starts accumulating at the inner surface of the cell membrane as it becomes favors positive potassium ion. This leads to development of negative potential at the outer side of cell membrane by the accumulation of negative ions or charges. Hence, a net negative potential membrane develops.
 
        
             
        
        
        
Hydrogen has one valence electron. To make it an ion, you need to remove this valence electron. When you remove an electron, the element becomes positive because you are taking away the negative
        
             
        
        
        
C. ferns.
Explanation:
The ferns are ancient plants that have managed to survive until the present. They are not closely related to the dominant plants nowadays, the flowering plants, but instead they are closely related with plants that have gone extinct tens and hundreds of millions years ago. Even though the ferns are not the dominant plants, they have managed to find a niche and firmly hold onto it, so they remained widespread, normally occupying the lower layers of the forests.
Unlike the flowering plants that produce flowers and then seeds in order to reproduce, that is not the case with the ferns. The ferns actually reproduce through spores, being widely dispersed by the wind and managing to spread out and reproduce over relatively large territory very quickly.
 
        
             
        
        
        
Answer:
D
Explanation:
Improve desirable traits and help determine the heritability of a trait.