As the product of ‘i’ gene binds with the operator region and blocks the transcription and translation of z, y and a genes. It’s product is prevented from binding to the operator by attaching it with the inducer. As the inducer can now no more capable of binding with the repressor, thus, in all the cases, operator always gets attached with the repressor thereby preventing the transcription and transmission of z, y and a. Even in the presence of lactose, transcription and translation of z, y and a would not occur.