The answer is “C”. Natural selection is about ones traits being better than another’s which allow it to survive in the wilds longer.
        
                    
             
        
        
        
The correct answer is HPA axis.
The Hypothalamic-Pituitary-Adrenal (HPA) axis is one of the most important neuroendocrine systems, which regulates the stress response and other functions such as the digestion, mood, emotions and the immune system. 
The hypothalamus, when triggered by a possible stressor, releases two hormones; the vasopressin and the corticotropin-releasing hormone (CRH). CRH, in turn, triggers the release of the adrenocorticotropin hormone (ACTH) from the pituitary gland. As a result of the secretion of ACTH, cortisol is secreted by the adrenal cortex. 
Cortisol is a steroid hormone, considered to be our body's stress hormone. 
        
             
        
        
        
The intensity of light had greater impact on the rate of photosynthesis. It was observed that the jar in which the intensity of light was high, large amount of oxygen was produced as compared to the jar in which the intensity of light was low.  
In the process of photosynthesis, oxygen is produced from the carbon dioxide. As the oxygen in the jar increases, the leaf disk rises with in the jar which also signifies the higher oxygen production with higher rate of photosynthesis in presence of high intensity of light.  
 
        
             
        
        
        
Answer:
True 
Explanation:
The stratosphere is the layer of the earth’s atmosphere which is above the troposphere and below the mesosphere.
The stratosphere contains about 90 percent of the ozone layer. The stratosphere is made up of ozone layers which helps in the absorption of about 95 percent of the ultraviolet rays from the sun and converting to heat. 
This is the reason why depletion of the ozone layer found in the stratosphere gives rise to global warming.
 
        
             
        
        
        
C. The organism would slow down its breathing, so that the heart could recover.