A) accumulating inside the cell until enough is present to bind repressor proteins and stop transcription. B) accumulating inside the cell until enough is present to bind activator proteins and initiate transcription. C) interacting with small RNAs to either inhibit or enhance transcription. D) diffusing out of the cell and when a critical cell density is reached, moving back in and binding to a regulatory protein to initiate transcription. E) being synthesized after glucose is used up, thereby bypassing catabolite repression.