Which of these operons is most similar to the lac operon? Explain.

Molecular biology, please explain in detail

consider the fec operon of Staphylococcus madeupiddis, which encodes an iron citrate uptake system.  The fec operon promoter, called “Pfec”, is normally off when no regulators are bound to it (like the lac operon promoter).  The activator FecA senses iron citrate and brings the appropriate enzyme to Pfec to start fec transcription when iron citrate levels are high.  The repressor FecB senses free iron atoms and prevents fec transcription when free iron levels are high by binding to an operator between the promoter and structural genes. Considering the fec operon described above, which mutation would result in the operon being off under all conditions? Deletion of the operator where the repressor FecB binds to the DNA Deletion of the gene encoding the repressor FecB None of these mutations would result in the operon being off under all conditions Deletion of the gene encoding the activator FecA