Which is an arrangement of genes consisting of an operator, a promoter, and a repressor?

The correct answer would be operon.

Operon can be defined as a functional unit of the DNA which consists of structural gene and regulatory element such as promoter, operator, and repressor.

It may contain many structural genes under the control of single promoter. All the genes are transcribed as single mRNA which undergoes different types of splicing to produce different functional proteins.

For example, lac operon contains three functional genes lac Z, lac Y, and lac A together with promoter and operator sites.

i would say the prokaryotic cells the prokaryotic cells are less complex, are usually found only in unicellular organisms and have more limited capabilities than eukaryotic cells.

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