Final answer:
DNA methylation is not involved in post-transcriptional control; this process is related to transcriptional regulation and occurs at the DNA level, not on the RNA.
Step-by-step explanation:
The component not involved in post-transcriptional control is b) DNA methylation. Post-transcriptional control includes mechanisms that occur after the RNA molecule has been created but before it is translated into protein, and involves a variety of processes including the control of RNA splicing, RNA shuttling, RNA stability, and the activity of microRNAs and RNA interference. DNA methylation, on the other hand, is a form of epigenetic regulation that generally affects transcriptional control rather than post-transcriptional events.