So if we are to label these carbons here, this is carbon number one, carbon number two, carbon number three, four and five. And so this three position carbon contains a free hydroxyl group that can nucleophilically attack this phosphorus atom of this triphosphate group. And this is the phosphodiastic bond that is formed that we spoke about earlier. So essentially, we have the DNA polymerase essentially hoving over this molecule. And when this nucleotide so this is one of the dNTP nucleotides that we spoke about earlier. The dNTP molecule comes in close proximity as long as this base is complementary to this base.