Which of the following statements is considered incorrect? select one: a. if all the enzymes that a cell will possibly need are produced all the time, then a cell will waste a lot of energy. b. the transcription of beta-galactosidase is regulated by the presence or absence of lactose in the environment. c. when lactose is present, it binds to the repressor region of the lac operon, thereby causing a conformational change of the repressor and making it fall off from the operator region. d. lactose is the only energy source that bacteria can utilize. e. the enzyme beta-galactosidase catalyzes the hydrolysis of lactose into galactose and glucose.