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
Which type of RNA has the highest percentage of modified base ? 
Select and explain. 
A. mRNA, B. tRNA, C. rRNA, D. snRNA
B: tRNA
Answer: B: tRNA 
Explanation: In eukaryotic cells, 10-20% of the bases in tRNA may be modified and known as modified or unusual bases.