Answer:
D) Habitats for animals.
Explanation:
 It depends what the question means when it says 'the changing of the rivers'. I took it as the rivers are changing size and becoming more spread out. In that case, I chose habitats.
 The more water there is, the more habitat there is for sea life.
 All in all, the correct answer is D).
 
        
             
        
        
        
<span>The correct answer is horizontal gene transfer, transduction.</span>   
Transduction (a type of horizontal gene transfer)is the process by which foreign DNA is introduced into a bacteria cell. When viruses infect bacterial cells, their DNA is integrated into a bacterial chromosome and thus harness the replicational, transcriptional, and translation machinery of the bacteria. As a result, bacteria cell makes numerous virions (viral particles).
        
             
        
        
        
Answer/Explanation:
b) kidney and bladder
Kidneys are the main organ in the excretory system and the bladder stores the urine in the body. These are two of the organs that make up the excretory system.  
 
        
             
        
        
        
Answer: C - spiral staircase 
Explanation: