The answer is stroke. This means that formation of plaque in the blood vessels that serve the brain cause thickenning of the inner walls of the vessels. When the plaque ruptures, a blood clot forms and blocks blood passage to a particular region of the brain served by the vessel. This stifles oxygen supply to the respective part of the brain leading to the death of the cells in the region.
 
        
             
        
        
        
Answer:
Explanation:
It upsets the natural food webs in the area
i think B is the answer.. 
sorry if its not.
 
        
                    
             
        
        
        
Answer:
They are not violent killers because they need their host to stay alive for their benefit And if the host dies the parasite wont have a host so they try to keep it alive for as long as possible.
Explanation: