Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA<span>). Passed from parents to offspring, </span>DNA<span> contains the specific instructions that make each type of living creature unique.</span>
        
             
        
        
        
Answer:
<em>Option "A" might be the correct answer</em>
<em>Explanation:</em>
<em>there are some of those viruses where it can be quite potent. Some viruses, such as the rhinoviruses, seldom cause serious illness. But others, such as parainfluenza and respiratory syncytial virus, can lead to severe lung infections in young children.</em>
 
        
                    
             
        
        
        
Answer:
Cross-pollination.............