Answer:
Phosphodiester bonds.
Step-by-step explanation:
DNA is the genetic material of the almost all the organism. The DNA is made of the polymer of nucleotides that contains the nitrogenous bases, pentose sugar and the phosphate molecule.
The DNA is a double stranded molecule that contains two DNA strands. The two strands are joined together through the phosphodiester bond. This bons is a type of covalent bond that joins the two strand together.
Thus, the correct answer is covalent bond.