Answer:
Step-by-step explanation:
hydrogen bond is a bond that is formed as a result of intermolecular forces that exist between hydrogen
and other atoms of electronegative elements such as oxygen and carbon. Since covalent bond is more stronger than hydrogen bond, with this it helps to hold DNA , proteins, molecules together, it brings about the stability of the double helix structure of DNA.
Therefore,it is useful for the base pairs of DNA to be held together by hydrogen bonds and not covalent bonds because Hydrogen bonds are crucial in DNA synthesis. and also it very easy for hydrogen bonds to be broken than covalent bonds. As a result of this, DNA can be easily unwind.