An ecological niche is an organism's specific habitat in an ecosystem.
It is where it lives and feeds, etc.
        
                    
             
        
        
        
Obesity and genetic factors is usually a strong risk factor for many different diseases and it's no difference in this case - people/women who are obese and have a family history of breast cancer also possibly have a higher likelihood of developing it themselves. 
        
             
        
        
        
23.15..............................
        
             
        
        
        
Answer The stomach secretes acid and enzymes that digest food. Ridges of muscle tissue called rugae line the stomach. The stomach muscles contract periodically, churning food to enhance digestion. The pyloric sphincter is a muscular valve that opens to allow food to pass from the stomach to the small intestine.
Explanation:
 
        
             
        
        
        
The correct answer is habitat destruction :)