Which nitrogenous base pairs with thymine (T) in a DNA molecule?

In a DNA molecule, thymine (T) pairs specifically with adenine (A) through two hydrogen bonds. This base pairing is a fundamental aspect of the structure of DNA, which maintains the stability of the double helix shape. The complementary pairing between A and T ensures that information encoded in the DNA can be accurately replicated during cell division and expressed during protein synthesis.

In contrast, cytosine (C) and guanine (G) form a different pairing, connected by three hydrogen bonds. Uracil (U) is not present in DNA; rather, it is found in RNA, where it pairs with adenine instead of thymine. Therefore, the correct pairing for thymine in DNA is with adenine, making it the correct answer.