A. prevent cross-contamination.
        
             
        
        
        
Answer:
False.
Explanation:
Pseudoscience are not exact and precise. In fact, they are mistaken practices/methods that are not part of the scientific method or based on the scientific method.
 
        
                    
             
        
        
        
Answer:
That black, sooty-looking substance on the skins of onions is indeed a mold, specifically, Aspergillus niger. It is common on onions, both in the field and once dried, bagged and stored. The fungus typically is found on the outside skins of an onion, and it is harmless, for the most part.
 
        
             
        
        
        
Answer: a mutagens d carcinogens b point mutation c frameshift e missense f nonsense
Explanation: Hope that helps!