Which of the following RNA contains a dihydrouridine arm?

The dihydrouridine arm or the D-arm is present in the tRNA or the transfer RNA. Dihydrouridine is a modified pyrimidine base found in the tRNAs of the prokaryotes, eukaryotes, and in some archaea. The formation of dihydrouridine is catalyzed by the enzyme Dihydrouridine synthase. The modified base is formed by the reduction of the uracil (C=C double bond at positions 5 and 6) with flavin mononucleotide as a cofactor. 

The dihydrouridine is mostly found in the D-loop of tRNAs. The D-loop of the tRNA is named due to the modified dihydrouridine base. The numbers of dihydrouridines is varying in different tRNAs. The Dihydrouridine base on the D-loop forms a hairpin structure in the tRNA. The hairpin structure plays an important role in the folding and stability of tRNA.