Which of the following pairs of bases are complementary in RNA?

In RNA, the complementary pairing of bases occurs according to specific rules. Adenine pairs with Uracil, while Guanine pairs with Cytosine. This is essential for the processes of transcription and translation in protein synthesis.

Adenine and Uracil are both pyrimidines, with Uracil replacing Thymine, which is found in DNA. This unique pairing allows the RNA to maintain its structure and function properly during cellular processes.

The other options feature pairs that do not align with the complementary base pairing rules of RNA, thus reinforcing why adenine and uracil are the only correct pairing in this context. Understanding the specific base pairings is fundamental in studying nucleic acids and their roles within biological systems.