Answer:Negative inducible and Negative Repressible
Step-by-step explanation:
Negative control of operon includes Negative inducible and Negative repressible both prevent transcription, but are different in there mode of operation.
Negative inducible operon: This is usually a process by which an active repressor regulatory protein binds to the DNA thereby inhibiting RNA polymerase from transcribing gene.
Negative repressible operons: This is also a process when an negative inducer binds to the operator to which prevent DNA transcription