According to the wobble hypothesis, a U in the 5' position of the anticodon can pair with which of the following?

The wobble hypothesis articulates that the pairing between the anticodon of tRNA and the codon of mRNA is not always strict, allowing for some flexibility in base pairing. Specifically, when a uracil (U) is in the 5' position of the anticodon, it can pair with adenine (A) or guanine (G) in the corresponding codon. This means that a tRNA carrying U in its anticodon can recognize both codons that end in A or G, which is crucial for the efficient translation of proteins.

This flexibility helps to accommodate the genetic code's redundancy, where multiple codons can encode the same amino acid. The ability of uracil to pair with A or G supports this phenomenon, enabling a degree of variability that is fundamental to protein synthesis. The correct pairing options highlight this unique feature of nucleotide interactions that contributes to the robustness of the genetic message.