Operon
Step-by-step explanation:
The possible explanation of the increased synthesis of the protein by an occasional mutation in the promoter is that the mutation could occur in the enhancer sequence
This specific region, enhancer are 200 base pair long DNA elements that is present either upstream or downstream to the transcriptional start site
Activity of enhancer is orientation independent and provide binding site for activators(activators are large proteinaceous complex that initiate transcription)