A would be your answer! Have a great day love! 
        
             
        
        
        
Answer:
Substances
0 (most acidic)	Hydrochloric acid (HCl)
1	Stomach acid
2	Lemon juice
3	Cola, beer, vinegar.
Examples of alkaline are:sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide etc
 
        
             
        
        
        
Answer:
This is an example of founder effect. 
Explanation:
Founder effect may be illustrated as the loss of genetic variation in a novel small population originated from the original population. The concept was initially presented by Ernst Mayr. It can be seen that genetic diversity has got reduced in the population of iguana due to the result of the flood that has washed all the iguana without webbed feet into the sea.  
The new population has got inclined from the small iguana population. Thus, the iguana population is regarded as an illustration of the founder effect.  
 
        
                    
             
        
        
        
The actual answer is, "A", an ocean trench.
You can find out more about them by researching them up on Google, it's only a few phrases and a hit on the enter key :P
        
             
        
        
        
I think it’s called the passer.