This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of nucleic acids, Subject name: Biochemistry
[{'content': 'Abnormal base in tRNA is \nSelect and explain. \nA. Dihydrouracil, B. Orotic acid, C. Methyl Xanthine, D. Cystine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The D Arm or DHU region is so named due to the presence of a dihydrouridine in that areaThe DHU arm serves as the recognition site for the enzyme which adds the amino acidRef: DM Vasudevan, 7th edition, page no: 597', 'role': 'assistant'}]