Answer:
Option (B).
Explanation:
Neurons or nerve cell are the basic structural and functional unit of the nervous system. Fibers are the thread like long projection of the nerve cells. 
Neurons are classified into three fibers- Group A fibers, B fibers and C fibers. The group C fibers cannot capable of doing the saltatory conduction of the nerve impulse because they are unmyelinated.
Thus, the correct answer is option (B).
 
        
             
        
        
        
The answer is H. He is mechanically digesting his food.
        
                    
             
        
        
        
Answer:
A spade placed in the fire turns hot.
Explanation:
 
        
             
        
        
        
Evidence for evolution is provided by homologous structures. These are structures shared by related organisms that were inherited from a common ancestor. Other evidence for evolution is provided by analogous structures.