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
The process which occurs over cytidine residuces and often results in gene inactivation is 
Select and explain. 
A. Gene rearrangement, B. Pseudogene formation, C. Histone acetylation, D. DNA Methylation
D: DNA Methylation
Answer: D: DNA Methylation 
Explanation: Mnemonic: DNA Methylation mates the DNA Mute.
Refer the byte " Post transcriptional modification"