Answer:
Pancreas. 
Explanation:
Pancreas is an organ that acts as both exocrine as well as endocrine gland. As exocrine gland, it secretes digestive enzymes into the small intestine that help in digestion of complex food molecules. 
As an endocrine gland, it secretes glucagon (from alpha cells) and insulin (from beta cells) hormones, directly into the bloodstream. Both of these hormones are responsible for the regulation of blood sugar level in the body. 
Thus, the correct answer is 'pancreas.'
 
        
             
        
        
        
 Natural selection<span> is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations.</span>
        
                    
             
        
        
        
Fruits contain acids that make them sweet!
        
             
        
        
        
You should typically give ventilation’s to a young child every 30 seconds. 
Hope I could help! :)