In DNA, which bases pair with each other?

In DNA, the base pairing rules are established by the structure of the nucleotide bases. Adenine (A) pairs specifically with thymine (T) through two hydrogen bonds, which creates a stable and complementary pairing essential for DNA's double helix structure. In addition, guanine (G) pairs with cytosine (C) through three hydrogen bonds, providing even greater stability to the DNA molecule due to the stronger interaction.

This specific pairing is crucial for the accurate replication of DNA and the transmission of genetic information. The complementary nature of adenine with thymine and guanine with cytosine ensures that when DNA is replicated, each strand serves as a template for the creation of a new complementary strand, maintaining genetic fidelity.

In contrast, the other combinations presented do not reflect the established pairing rules within DNA. For example, pairing adenine with cytosine or guanine with thymine is not correct according to the Watson-Crick model of DNA structure. Similarly, the pairing of adenine with guanine and thymine with cytosine does not align with the known base pairing mechanisms. Lastly, the pairing mentioned in one option includes uracil (U), which is found in RNA, not DNA.

Thus, the most accurate