The herpes virus infects the humans to cause chickenpox disease. The virus during its stage of causing infection, it spreads through the epidermal cells by infecting them. This causes the typical rash on skin that is seen in chickenpox. The virus then enters that sensory nerves present on the ski and travels along the length of the neurons to the sensory dorsal-root ganglia adjacent to the spinal cord. Here the virus stays in an inactive stage.
 
        
             
        
        
        
Answer:
Abscisic acid.
Explanation:
Also written as ABA.
Act as Growth inhibitor.
Sorry if I write wrong spelling of abscisic acid. (But I think it's right)
 
        
             
        
        
        
The correct answer is fixed migration pattern.
Extinction means termination of last member of a particular species. This can be due to various factors. The reason could be natural or human interventions. The best characteristics of an organism to be less likely to face extinction are the fixed migration pattern. Migration of that particular species in a fixed pattern will make them adapt different environment. This saves the species from natural extinction. Even if the species of a particular geographical area dies the migrated species will be alive to breed and save the species from extinction.
 
        
                    
             
        
        
        
More than likely mutation