The correct answer is option C, that is, behavioral isolation.  
The phenomenon of behavioral isolation takes place when two populations possess the tendency of interbreeding, but exhibit distinctions in courtship rituals or other kinds of behavior. For example, the western and eastern meadowlarks are very identical birds whose habitat overlap in the middle of the United States.  
However, the members of the two species will not mate with each other, possibly as they use different songs in order to fascinate males. The eastern meadowlarks will not respond to the songs of western meadowlarks, and vice versa.  
 
        
                    
             
        
        
        
The answer is B. They are both made up of subatomic particles.
        
                    
             
        
        
        
The Trout are probably not used to the water and their surroundings.
        
             
        
        
        
Answer: I think the answer is C.
Explanation:
 
        
             
        
        
        
Answer: Hi.... I hope it helps!!
Skin Pigmentation in humans
 
Explanation: Polygenic inheritance- It is simply a single characteristic which is controlled by more than two genes.  Human skin's color is determined by the amount of dark pigment it has which is melanin
. Minimum four genes are involved in the melanin production.
It is a case of continuous variation as the combination of melanin producing allele are responsible for degree of pigmentation