Which of the following schematics correctly depict a lac operon that can be negatively regulated?

Step-by-step solution

For a lac operon to be negatively regulated, the repressor protein (synthesized by the regulatory gene i ) must be able to bind to the operator ( O ) and block RNA polymerase from transcribing the structural genes. This mechanism requires the operator ( O ) to be located immediately downstream of the promoter ( P ) for the structural genes, so that repressor binding physically obstructs transcription. Evaluating the given schematics: In schematic (i), the arrangement is P-i-P-O-z-y-a . The operator O is correctly p