The hydrogen bonding of nucleotides into a new DNA molecule is facilitated by enzymes. Hydrogen bonding is the electromagnetic attraction between polar molecules in which hydrogen is bound to a larger atom, such as oxygen or nitrogen. The nucleotides in a base pair are complementary which means their shape allows them to bond together with hydrogen bonds. The A-T pairs forms two hydrogen bonds while the C-G pair forms three. The enzymes called DNA polymerases join the nucleotides by way of phosphodiester bonds. 
        
             
        
        
        
Answer:
Resident microflora b. may be responsible for opportunistic infections in immunocompromised
Explanation:
It is almost impossible to found these microorganisms in the stomach because of the acidic conditions, most of them are not adapted to this type of environment. Resident microflora is not transient, is actually permanent. However, resident microflora may be responsible for ooportunistic infections in immunocompromised and they can also increase the intensity of the disease produced by that pathogen.
 
        
             
        
        
        
Answer:
C. Outer Core
Explanation:
a good thing to remember is that the inner core is solid and the outer core is liquid