Biochemistry The ZYA region of the lac operon will be maximally expressed if: A Cyclic AMP levels are low B Glucose and lactose are both available C The attenuation stem-loop is able to form D The CAP site is occupied and the operator site is free 💡 Explanation The ZYA region of the lac operon will be maximally expressed if: ✓ Correct Answer: D. The CAP site is occupied and the operator site is free