One of the following best describes the cap modification of eukaryotic mRNA

• A. Modified guanine nucleotide added to the 3’ end of the transcript
• B. Modified guanine nucleotide added to the 5’ end of the transcript
• C. String of adenine nucleotides added to the 3’ end of the transcript
• D. String of adenine nucleotides added to the 5’ end of the transcript