DNA Polymerase Catalyzes Phosphodiester Bond Formation

Steps:

• Recall DNA replication involves enzymes building new strands from a template.
• Identify DNA polymerase as the enzyme that adds nucleotides to the growing chain.
• Note it links nucleotides via phosphodiester bonds in the sugar-phosphate backbone.
• Eliminate options not matching this core function.

Why C is correct:

• DNA polymerase forms phosphodiester bonds between the 3' OH of the growing strand and the 5' phosphate of incoming nucleotides, completing the backbone per the mechanism of semi-conservative replication.

Why the others are wrong:

• A: Condensation reactions produce nucleotides beforehand; DNA polymerase uses pre-made ones.
• B: RNA nucleotides align via base pairing, but DNA polymerase works with deoxyribonucleotides on DNA templates.
• D: Glycosidic bonds form during nucleotide synthesis, not by DNA polymerase; it handles phosphodiester bonds, while base pairing is hydrogen bonding.

Final answer: C