From my speculation it is loss of habitat and global warming
        
                    
             
        
        
        
Answer:
<em>The correct option is B) the total variety of organisms on Earth</em>
Explanation:
Biodiversity can be described as the diversity or variety of life present on Earth. The variety of plants and animals which are located in different habitats make up the biodiversity. Biodiversity is the reason that different variety exist between members of a species. Biodiversity tends to favour those organisms which are better adapted to live in an environment. These organisms tend to pass on their characteristics to their offsprings and become more in number. 
 
        
                    
             
        
        
        
Answer:
Pinocytosis is one type of endocytosis, the general process by which cells engulf external substances, gathering them into special membrane-bound vesicles.
Explanation:
Hope that helped!
 
        
             
        
        
        
I believe its aerobic respiration
        
             
        
        
        
Substance A is water and Substance B is chlorophyll