Answer:
The most appropriate answer would be The cell will not make functional proteins from that mRNA strand.
The amino acid sequence of the proteins is derived from the nucleotide sequence of the mRNA (messenger ribonucleotide).
If the sequence of mRNA is miscopied, it will change the sequence of amino acids of the protein.
Consequently, the protein may become non-functional. 
 
        
                    
             
        
        
        
The best answer is  B - Proteins.
Proteins make up enzymes, or to put it another way enzymes are made up of protein. It is enzymes that speed up the chemical reactions. Enzymes are organic catalysts, substances that speed up a (biochemical) reaction but do not take part in the reaction and remain unchanged at the end of the reaction.
In man, there are many enzymes. The majority of these are found in the digestive system where they greatly aid the process of food breakdown from complex molecules to simple molecules. Examples include salivary amylase found in saliva,  which begins the gradual breaking down of starch into glucose right from the moment food is placed in the mouth and mixed with saliva. Pepsin in the stomach breaks down protein.
 
        
             
        
        
        
Patent ductus arteriosus occurs when the normal fetal circulation conduit between the pulmonary artery and the aorta fails to close and results in increased pulmonary blood flow. The clinical manifestations of patent ductus arteriosus include; Murmur; wide and bounding pulse pressure, Asymptomatic Heart failure.