DNA polymerase catalyzes the joining of a nucleotide to a growing DNA strand.What prevents this enzyme from catalyzing the reverse reaction?

A)hydrolysis of pyrophosphate (PP_i) to inorganic phosphate (P_i) + P_i
B)release of PP_i from the nucleotide
C)hybridization of the new strand to the template
D)loss of ATP as an energy source