Answer:
the answer is U shaped valley
 
        
                    
             
        
        
        
Answer: alleles
Explanation:
Alleles are different forms of a given gene. Alleles are mutated forms of a given gene which controls a particular trait. For instance, the gene that codes for hemoglobin is denoted with the letter A but the gene has another variant denoted by S. In abnormal hemoglobin S (sickle hemoglobin), glutamate is replaced by valine at position 6 in the amino acid sequence of the two beta chains of hemoglobin. This change in the amino acid sequence causes the red blood cells to have a sickle shape resulting in sickle cell disease. Therefore hemoglobin A and S are alleles of a given gene. 
 
        
             
        
        
        
D would be the answer to this question
        
                    
             
        
        
        
I would say C or D
Hope This Helps
        
                    
             
        
        
        
Answer:
You didnt give me and choices so out of the information i have from this answer i can conclude that the answer is out of these 3 Options.
1.) Phyllids 2.) Xylem 3.) Phloem