Which of the Following Reaction Sequences Best Describes the Formation

Which of the following reaction sequences best describes the formation of the nucleic acid in the biosynthesis of DNA?

A) nucleophilic attack of a 5'-OH group of one nucleotide on the β-phosphorus of another
B) nucleophilic attack of a 5'-OH group of one nucleotide on the α-phosphorus of another
C) nucleophilic attack of a 3'-OH group of a nucleotide on the γ-phosphorus of another
D) nucleophilic attack of a 3'-OH group of one nucleotide on the β-phosphorus of another
E) nucleophilic attack of a 3'-OH group of one nucleotide on the α-phosphorus of another