This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': "Which of the following is true about capping of RNA following its synthesis \nSelect and explain. \nA. Occurs at 3' end of RNA, B. Occurs in nucleus of cell, C. Specific to MRNA of Prokaryotes, D. S-adenosyl methionine (SAM) acts as methyl donor", 'role': 'user'}, {'content': 'Answer: D \nExplanation: 7 - Methylguanosine attached to 5\' end of RNA is called capping of RNA.\nRefer byte "Post transcriptional modification".', 'role': 'assistant'}]