Operons are switched on/off by
question 2 options:

operators

promotors

rna polymerase

Answer;

Operators

Explanation;Operator is the regulatory switch which is a segment of DNA, usually positioned within the promoter. An Operon is the entire stretch of DNA that includes the operator, the promoter, and the genes that they control.  it is a set of genes transcribed under the control of an operator gene. An operon is a functional unit of transcription and genetic regulation. The promoter is the binding site for RNA polymerase, the enzyme that performs transcription. The operator is a regulatory site bound by a repressor protein.

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