<span>B. Marsupials. </span>Amniotic eggs is a unique kind of egg because they possess a semipermeable shell to protect the egg but it also allows gas exchange. Inside an amniotic egg contains the amnion, chorion and allantois. Animals that lay amniotic eggs are called amniotes, which include reptiles, birds, dinosaurs, monotremes (platypus).
        
             
        
        
        
Answer:
all of their cells grew larger
 
        
                    
             
        
        
        
A seems most probable. 
Oceans are also deeper and larger then Seas.