Weak hydrogen bonds between the nitrogenous base pairs hold the two strands of DNA together. Why are the strands held together by weak hydrogen bonds instead of covalent bonds

Explanation:

Hydrogen bonding is usually occur wen interaction with hydrogen atoms occur.

Hydrogen bonds joins DNA polymers because an hydrogen atom occur on on one base which is called hydrogen bond donors and another oxygen or nitrogen atoms on the base across from it which is called hydrogen bond acceptors.

Adenine “A” a purine and Thymine “T” a pyrimidine each have a donor and one acceptor, whereas Cytosine “C” a pyrimidine has one donor and two acceptors, and Guanine “G” a purine has one acceptor and two donors.

This atoms allows for hydrogen bond between them that gives them structure of DNA molecule.

A nucleotides is hydrogen bonded to T nucleotides while C nucleotides is hydrogen bonded to G nucleotide this is called complementary base pairing.

i believe the answer is a or 1