Final answer:
When lactose is present, a repressor binds to the operator region preventing RNA polymerase from transcribing the genes involved in lactose digestion. This statement is true.
Step-by-step explanation:
True. When lactose is present, it binds to the repressor protein, causing a conformational change that removes the repressor from the operator region of the lac operon. This allows RNA polymerase to bind to the promoter and initiate transcription of the genes involved in lactose digestion.