Answer:
The correct answer is e. All of the above.
Explanation:
Sister chromatids are made during the synthesis phase of the cell cycle. In the synthesis phase, the homologous chromosomes get replicated and sister chromatids are produced so they are produced by duplication of chromosomes.  
As sister chromatids are produced by replication, therefore, they are identical copies of parent chromosomes. These sister chromatids are joined to each other at centromere. They get separated during the anaphase of mitosis and moves to the opposite pole. 
Therefore the right answer is e. 
 
        
             
        
        
        
DNA<span> and </span>RNA<span> are both comprised of nucleotides that bind to a sugar backbone. The </span>DNA<span> nucleotide </span>bases<span> include adenine, cytosine, guanine and thymine. The </span>RNA <span>nucleotide </span>bases<span> include adenine, uracil, guanine and cytosine.</span>
        
                    
             
        
        
        
Forceps, they literally are almost the exact same thing.
        
                    
             
        
        
        
If you used a full active virus, that defeats the point of a vaccine. You will trigger your immune response, but since you would just be injecting the virus, it will make you sick, and your body will be less effective at fighting the pathogens. 
Viruses in vaccines are weakened, so they essentially will not "fight" back. They most importantly just contains the antigen markers so the body can trigger the immune response, quickly eradicate the pathogen, and build up the memory cells to that virus. 
Injecting a virus that is not weak will just be the same thing as if you got the virus, you will likely get sick.