I think it is A because they can just destroy it but D is finding something natural to kill it off but it is GM so it wouldn't help so A
        
             
        
        
        
The changing quantities in an experiment are called variables. A variable refers to any trait, factor, or a condition, which can prevail in distinct amounts or kinds. An experiment generally exhibits three kinds of variables: independent, dependent, and controlled.
The independent variable refers to the one, which is modified. On the other hand, the dependent variable is implied to observe that how it reacts with the change made to the independent variable. The controlled variables refer to the quantities, which one wants to remain constant.
In the given case, that is, heating a cup of water to witness that whether the sugar will get more easily dissolve. In this, the independent variable refers to the temperature of the water determined in degrees Centigrade. The dependent variable refers to the amount of sugar, which dissolves completely measured in grams.
In this, the controlled variables are stirring and type of sugar. As more stirring might elevate the amount of sugar that dissolves, and different kind of sugars might dissolve in distinct concentrations. So, in order to make sure a fair test, there is a need to keep these variables similar for each cup of water.
 
        
             
        
        
        
 Orographic lift occurs when an air mass is forced from a low elevation to a higher elevation as it moves over rising terrain. As the air mass gains altitude it quickly cools down adiabatically, which can raise the relative humidity to 100% and create clouds and, under the right conditions, precipitation
 
        
                    
             
        
        
        
Answer:
The answer is C
Explanation:
Soil is rock but broken down into tiny rock.
Hope this helps    :)