31. What is the molecular event by which the operator of an operon regulates the expression of its
structural gene(s)?
(A) The operator codes for the repressor, which binds to the structural genes
(B) The operator codcs for the repressor, which binds to the RNA polymerase
(C) The operator is bound by the repressor, thereby inhibiting RNA polymerase
(D) The operator is bound by the regulator gene, thereby inhibiting RNA polymerase