Klinfelters syndrome is when there is an extra X chromosome in males.
So instead of the normal sex chromosomes for males (XY), a male with klinefelters syndrome will have XXY.
I have included a pic of the karyotype to give you a better idea of what I'm talking about.
Hope this helps! I'm happy to help with any other questions you might have :)
 
        
        
        
The answer is c because the precession of the ecliptic was component of a milankovitch cycle  and is related to periodic ice ages through out history
 
        
                    
             
        
        
        
Mice...........................................
        
             
        
        
        
According to the Big Bang theory, the universe was once very dense and is now expanding.