A particular E. coli cell contains a lac operon that continuously breaks down lactose into glucose and galactose. What could be a possible explanation for this occurrence? Select one: a. Beta-galactosidase is being inhibited by an allosteric inhibitor. b. The I gene in the lac operon is mutated and does not encode for the lac repressor. c. This particular E. coli cell does not use glucose as a viable sugar source. d. The lac repressor has a mutation in the lactose binding site. e. The operator has a mutation that does not allow the RNA polymerase to bind to it.