The U2 snRNA basepairs with
nucleic acid structure and recombination analysis shows hairpin formation, Holliday junction resolution and translation control ensure fidelity. Consequently the branched sequence in the intron emerges as the valid choice since it matches molecular mechanisms, aligning with established principles in molecular biology literature.
Ref: Lodish et al., Molecular Cell Biology, 8th Edition, Chapter 8, RNA Processing and Translation, covers mRNA hairpins, puromycin mechanism and aminoacyl-tRNA function governing protein synthesis.
