Gene regulation governing lactose operon of E.coli that

Gene regulation governing lactose operon of E.coli that involves the lac I gene product is:

1. Negative and inducible because repressor protein prevents transcription
2. Negative and repressible because repressor protein prevents transcription
3. Feedback inhibition because excess of b-galactosidase can switch off trascription
4. Positive and inducible because it can be induced by lactose

Lac operon under control of repressor shows a negative regulation. Operon has inducible nature.