54. A mutation that inactivates the regulatory gene of a repressible operon in an E. coli cell would result in
(A) complete inhibition of transcription of the structural gene controlled by that regulator.
(B) continuous transcription of the structural gene controlled by that regulator.
(C) irreversible binding of the repressor to the operator.
(D) inactivation of RNA polymerase by alteration of its active site.
(E) continuous translation of the mRNA because of alteration of its structure.