Scientific law.
A scientific law describes something in nature and predicts how it will behave without explaining.
This is because before a scientific law has been made, numerous observation has been done under different situations. The scientific law is established when a natural event invariable occur given a set of circumstances. 
        
                    
             
        
        
        
Answer:
The answer is C.
Explanation:
The submentovertex or the full basal projection of the skull is used best to demonstrate the base of the skull or the base of cranium. In this method, the x-rays' direction is starting from under the chin and exiting at the vertex or the top of the skull.
I hope this answer helps.
 
        
                    
             
        
        
        
Placenta
It also does not allow the maternal and fetal bloodstreams to mix
        
             
        
        
        
Polysaccharide formation allows organism to store energy efficiently. The storage form of food in animals is glycogen and in plants it is starch. Both glycogen and starch are polysaccharides of glucose. Many glucose units are linked together by condensation reaction to form polysaccharide. Compared to having several molecules of glucose in a bulk it is better to store it in the form of condensed bulk i.e polysaccharide. Thus polysaccharides which are formed by condensation reaction i.e by the loss of water molecules are easy to store. 
Polysacchrides are: a) stored in the form of condensed bulk
b) they are chemically non-reactive
c) they are osmolytically inactive