<span>Populations of a short type of sunflower are identified as a new species under the conditions that </span>they are unable to breed with the sunflowers of the original population.
        
             
        
        
        
Answer:
the major factor is the decrease of deaths
 
        
                    
             
        
        
        
Answer:
The correct answer is "the bottleneck effect".
Explanation:
The bottleneck effect, also known as a population bottleneck or genetic bottleneck, is defined as sharp reduction of a species population that occurs either by environmental effects or as a consequence of human activities. The dramatical crash the that population of American bison had due to hunting and other problems is an example of a species suffering the bottleneck effect.
 
        
             
        
        
        
Any property that describes how a substance reacts with another substance when forming a new substance is the Property of Reactivity
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Explanation:
The ability of substance to readily react with other substance to produce new product is called as reactivity. 
It describes about different methods used by the reactants to form new product. 
Sometimes one single reactant gives rise to two different products as in splitting of water during which the following reaction takes place:
H_2 O →2H_2 + O
On contrary, two substance combines together to give rise to one single product as:
2 Mg + O_2  →2MgO