In wild-type E. coli, the lac operon can shift among three different states of transcription - i. e. basal, repressed, or activated - in response to the chemical composition of its environment. What effect would each of genetic changes listed below have on these 3 transcriptional states?

A. A mutation in the lacO operator DNA prevents it from binding LacI protein.

B. A mutation in the CAP binding site DNA prevents it from binding CAP protein.

C. A mutation in the lacI gene that prevents the LacI protein from binding to allolactose.

D. The wild-type lac operon core promoter matches the sigma 70 consensus sequence at 9 out of 12 base pairs (in the -10 and -35 sequences). Envision a mutation that causes the lac promoter to match consensus at 10 out of 12 base pairs. What effect would such a mutation have on the rate of lac operon transcription in each of the three states?