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. 
        
             
        
        
        
Answer:
The spread of corona virus was deadly and affected everyone, even if they weren't infected by the virus itself. Families were seperated, and thousands were killed. The world responded by sharing kindness and love to the people who need it most, and protecting itself by self isolation.
i hope this helps
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Region A, Hope this helps.
        
                    
             
        
        
        
Chemical weathring is most rapid in areas that warm and wet.
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Photon
        
                    
             
        
        
        
Answer:
4 is a great place to be your 
Explanation:
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