The following is an example for unusual base: (A) Di hydro uracil, (B) Adenine, (C) Cytosine, (D) Uracil
Answer is A. It is present in tRNAPresent in the DHU OR D arm of tRNAServe as the recognition site for the enzyme which adds the amino acidRef: DM Vasudevan, 7th edition, page no: 597