I think it’s because there’s very little oxygen flow to the brain. this causes abnormalities in the rhythm and pumping action of the heart. i don’t know if this will help you at all but hopefully it will?
        
             
        
        
        
Answer:
the right atrium.
Explanation:
Blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium.
 
        
             
        
        
        
Explanation:
is this an actual question!?? lol!
 
        
                    
             
        
        
        
The answer is d because i had the same problem yesterday in biology