1. No credible source
2. Check if its a biased answer
3. Examine evidence
The lac repressor protein is bound to the operator region of the lac operon when there is no lactose in the medium. When introduced in lactose, it binds to an allosteric site on the repressor causing its to change conformation and release from the operator. This allows the polymerase that is bound to the promoter region to proceed transcription of the lac operon genes (LacZ, Lac A, and Lac Y). Translation of these genes forms enzymes that enable the organism to break down lactose for energy.
It is The multicellular part
Hello!
The correct answer is A, more information is needed, because organisms from both the bacteria and archaea domains are prokaryotic and unicellular.
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