The answer would be C. Hope this helps buddy!!
        
                    
             
        
        
        
<span>They are proteins that are secreted from fat cells to help regulate energy balance.</span>
        
             
        
        
        
Answer: The population will evolve, leaving only those genetically equipped to deal with low oxygen levels. brainliest
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Answer:
More oxygen is needed to produce more energy, and more carbon dioxide waste must be removed from the body.
Explanation: