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 of the following doesn't occur during the processing of RNA? 
Select and explain. 
A. Terminal addition, B. Nucleoside modification, C. Nucleoside cleavage, D. Chemical hydrolysis
D: Chemical hydrolysis
Answer: D: Chemical hydrolysis 
Explanation: Precursor tRNA is processed to form mature tRNA. Alterations during processing are of three types: nucloelytic reactions, nucleoside modifications, terminal additions of nucleotides. Chemical hydrolysis is not a pa of RNA processing. Poly A tailing and 5'capping occurs in the processing of RNA. Methylation and deamination are known to occur. Introns will be removed after cleavage in the process.