<prompt> The ZYA region of the lac operon will be maximally expressed if:Cyclic AMP levels are lowGlucose and lactose are both availableThe attenuation stem-loop is able to formThe CAP site is occupied and the operator site is free  <response>: When the cAMP levels are low- there is no binding of CAP to CAP site. No ourable interaction for RNA polymerase. Lac operon is not expressed. - option a is excluded. When glucose is available, Lac operon is not expressed Attenuation is seen in tryptophan operon, not Lac operon For optimal expression of lac operon, The CAP site should be occupied the operator site should be free of repressor. 