I believe the answer is B, the survival of the fittest due to competition for resources. Survival of the fittest is a term that originated from Darwinian evolutionary theory was a way of describing the mechanism of natural selection. The biological concept of fitness is  defined as reproductive success. Many organism overproduce to increase chances of survival for their organisms due to competition. 
        
                    
             
        
        
        
1. four, bond
2. Cohesion 
3. Adhesion is correct ... looked in my bio book sorry
        
                    
             
        
        
        
Oxytocin and alcohol
Explanation:
Oxytocin helps to relax the muscles of the breasts and induce lactation in a breastfeeding mother. This hormone is commonly called the cuddle hormone since it helps to create the social and emotional bond between the child and the mother.
Alcohol clearly inhibits the secretion of oxytocin and breastfeeding immediately after alcohol consumption can reduce lactation and milk intake by the child. Maintaining an interval after an alcoholic drink again leads to delayed breastfeeding. Intoxicating levels of alcohol in breast milk can affect the child’s health.
 
        
             
        
        
        
The answer is D because <span>Restriction enzyme.</span><span> Restriction </span>enzymes<span> are used to cut </span>DNA<span> for later use in </span>biotechnology<span>.</span>
        
             
        
        
        
Answer:
The ecosystem would be forced to radically change, allowing new and possibly invasive species to populate the habitat.
Explanation:
A keystone species is an organism that helps define an entire ecosystem. Without its keystone species, the ecosystem would be dramatically different or cease to exist altogether. 
I HoPe ThIs HeLpS!!!!!