Which force can stabilize a DNA double-helix

A) Hydrophobic bases are found in the interior of the helix where each base pair is stabilized by the same number of hydrogen bonds. B) Hydrophilic sugar-phosphate groups are found on the exterior of the helix where they can interact with water. C) Non-covalent N-glycosidic bonds can form between nitrogenous bases in opposite strands in the helix. D) Covalent base-stacking interactions can occur between adjacent bases within the same strand in the helix.