Answer:
The preferable option will be - A.
A. similar environments and specific traits increased their chances of survival.
Explanation:
- The shark and dolphins have similar body shape and fins. But shark is a fish and dolphin is a mammal.
- Both of them are exposed to similar kind of environments. Both of them possess a specific kind of alternative characters and traits.  
-  So, Some species may have similar body structures even if they are not related because they evolved in similar environments and specific traits increased their chances of survival.
   
 
        
             
        
        
        
Surface waves cause most the the damage
        
             
        
        
        
Answer: true 
Explanation: In gel electrophoresis, the smaller the size/molecular weight of DNA the faster it moves across the gel and vise versa. This is as a result of the pore size of the gel which is usually prepared 1g of agarose in 100ml of distilled water. So a DNA fragment with 1000 base pairs will "struggle" its movement across the gel pore making it mive less faster and further. Movement and molecular weight of DNA are inversely proportional.
 
        
             
        
        
        
Answer:
A.  A parasite is an organism that lives on or in another organism and takes its food.
 
        
             
        
        
        
Answer:
Bacteria 
Explanation:
Bacteria are the dangerous organisms that can grow in a many different environments and are capable of producing toxic substances which can harm other organisms. This bacteria has the ability to survive in the most extreme environment present near the volcanoes. There are about 30,000 species of bacteria that can live in a variety of environments. There are also some bacteria that is beneficial to humans, animals and plants but they are less in number.