34. if the ratio nucleotides from one strand of DNA that act as template for transcript RNA are as a follow ratio \( T=25 A=13 \) \( \begin{array}{llll}\text { (A) } 25 & \text { (B) } 13 & \text { (C) } 15 & \text { (D) none of them }\end{array} \)

To solve this question, we need to understand how nucleotide pairing works in DNA and RNA transcription. In DNA, thymine (T) pairs with adenine (A), while in RNA, uracil (U) replaces thymine. The ratio provided, \( T=25 \) and \( A=13 \), shows that for every 25 thymine nucleotides in the DNA template, there are 13 adenine nucleotides. Since transcription converts DNA to RNA, every adenine in the DNA template will lead to a corresponding uracil in the RNA. Thus, the resulting RNA will have 13 uracil nucleotides paired with 13 adenine nucleotides. Looking at the answer choices: - (A) 25 corresponds to the original "T" count and is not relevant since we’re looking for how many nucleotides in RNA correspond to "A." - (B) 13 corresponds to the "A" count in DNA, which becomes uracil in RNA. - (C) 15 has no connection to any of the given nucleotides. - (D) None of them. Therefore, the answer is **(B) 13**.