Answer: C. The mutation resulted in a beneficial trait that enhanced survival.
Explanation: 
The bacteria was able to "evolve" and adapt to the Nylon being in its environment.
 
        
                    
             
        
        
        
Answer:
In the experiment conducted by Alisha to test the effect of different materials on the melting rate of ice, the dependent variable is the mass of the ice, and the independent variable is the type of cover material.
Explanation:
During an investigation or experiment, the dependent variable is the one whose changes will be studied, while the independent variable is able to influence the changes of the dependent variable.
In the case where it is wanted to <u>measure how different cover materials affect the rate of ice melting</u>, the dependent variable is the mass of ice and the independent variable is the coverage material, capable of affecting the time it takes for the ice to melt.
Learn more:
Dependent and independent variables brainly.com/question/967776
 
        
             
        
        
        
B. The U.S stock market crash and Franklin D Roosevelt’s policies
        
             
        
        
        
Answer:
Yes
Explanation:
The cerebral cortex, the largest part of the brain, is the ultimate control and information-processing center in the brain. The cerebral cortex is responsible for many higher-order brain functions such as sensation, perception, memory, association, thought, and voluntary physical action.
 
        
             
        
        
        
Answer:
cDNA library.
Explanation:
Genomic library may be defined as the collection of all the genomic DNA of an individual. The genomic library is constructed by the digestion of digestion of DNA fragments and there further transfer in the vectors.
cDNA library is prepared in case of eukaryotes because the complementary DNA is produced from the RNA. The eukaryotes DNA is interrupted with exons. In case of spider, the cDNA linrary is prepared because its DNA is interrupted with exons. 
Thus, the answer is cDNA library.