What is the role of glucose in regulating lac operon expression?

Select one:

a. It binds to the CAP protein, which causes CAP to bind to the DNA and help stabilize RNA polymerase at the promoter.

b. It binds to the lac repressor, which causes the repressor to fall off the DNA.

c. It regulates cAMP levels, which regulates CAP binding to the DNA.

d. It binds directly to RNA polymerase, which helps RNA polymerase bind at the lac promoter.