Answer:
3rd One
Explanation:
1. Doesn't even talking about animals dying
2. Kills of all the fish in one small pond but not the whole species
3. Correct because every individual in a species has been killed 
4. They just migrated not died
 
        
                    
             
        
        
        
I think the cell’s can become cancer cells but I’m sorry if it isn’t correct...
 
        
                    
             
        
        
        
Answer:
Wildlife Hazard 
Explanation:
Wildlife in dangerous place
 
        
             
        
        
        
Answer:
Different brands of nail polishes used by Sarah.
Explanation:
While conducting an experiment two different variables are considered namely dependant variable and independent variable. The variable which is continuously changed to see the effects is called as independent variable and the variable which is being tested is called as dependant variable. 
In the given scenario, Sarah want to know best brand of nail polishes which lasts longest without chipping. Thus the different brands of nail polish used by her is considered as independent variable.
 
        
             
        
        
        
Answer:
Of course, you could scan their driver’s license or look for signs of facial wrinkles and gray hair. But, as researchers just found in a new study, you also could get pretty close to the answer by doing a blood test.
Woman looking at herself in mirror That may seem surprising. But in a recent study in Nature Medicine, an NIH-funded research team was able to gauge a person’s age quite reliably by analyzing a blood sample for levels of a few hundred proteins. The results offer important new insights into what happens as we age. 
Explanation:
 For example, the team suggests that the biological aging process isn’t steady and appears to accelerate periodically — with the greatest bursts coming, on average, around ages 34, 60, and 78