Which of the following correctly describes how the two nucleic acid strands in DNA are held together?

• A. Covalent bonds between nitrogenous bases hold the two strands together.
• B. Ionic bonds between the sugar-phosphate backbones hold the two strands together.
• C. Hydrogen bonds between complementary nitrogenous bases hold the two strands together.
• D. Peptide bonds between nucleotides hold the two strands together.

Answer: (C)