I can't see the well but chemical changes happen when a substance combines with another to form a new substance. These processes are called chemical reactions and are not reversible except if you do more chemical reactions... So the well that is changing it's state of matter should be the one undergoing a chemical change. For, example boiling or freezing
 
        
             
        
        
        
Answer:
D
Explanation:
Lymphocytes are the second line of defence
First line of defence indiscriminately defends against all pathogens unlike secondary response which is targeted. First line of defence refers to the external body components like skin, secretions from the body in the alimentary canel 
Mucus traps pathogens. Stomach acid kills pathogens
 
        
                    
             
        
        
        
In ecology<span>, a </span>niche<span> (</span>CanE<span>, </span><span><span>UK:</span> <span>/<span>ˈniːʃ</span>/</span></span><span> or </span><span><span>US:</span> <span>/<span>ˈnɪtʃ</span>/</span></span>)[1] is the fit of a species living under specific environmental conditions.
<span>https://en.wikipedia.org/wiki/Ecological_niche</span>
        
                    
             
        
        
        
<span>Throughout the book Lily is going through a major spiritual transformation (just like the actual author). This causes her to begin with anger and hostility and to grow into a more understanding and forgiving person. Lily runs away from her bigoted home and is forced to make this spiritual transformation, which she does.</span>
        
             
        
        
        
Option C:
B. wild-type 5-AUGCAUACAUUGGAGUGA-3 mutant 5'-AUGCAUACAUCUGGAGUGA- 3' 
Explanation:
A frameshift mutation is a genetic mutation such that the triplet nature of gene expression by codons, the insertion or deletion occurs in such as way that it alters the complete sequence of 3 codon sets and can change the reading frame, resulting in a completely different translation from the original.
As it is pertinent to understanding that all genes are normally translated in sets of 3 codons, which typically describes and explain a unique amino acid sequence. Thus, if a frame shift mutation occurs, it can affect many amino acid sequences and finally the entire protein.  
If we look at option B:
wild-type 5-AUG   CAU  ACA  UUG  GAG  UGA-3  
mutant 5’-    AUG   CAU  ACA  UCU  GGA  GUG  A-3’  
An insertion of a base Uracil showed at the end of 3rd codon which affected and altered the whole sequence of codon triplets. This changed all next codons and finally all next amino acids will be altered.