Which is target for the attachment of repressor protein produced by the regulator gene?

Options

A. Promoter
B. Inducer
C. Operator
D. Structural gene

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the target for the attachment of a repressor protein that is produced by a regulator gene.

2. **Identifying the Role of the Repressor Protein**: Repressor proteins are regulatory proteins that bind to specific sites on DNA to inhibit the expression of genes.

3. **Locating the Binding Site**: The specific site on the DNA where the repressor protein binds is known as the **operator**.

4. **Describing the Operator**: The operator is a segment of DNA that is typically located downstream of the promoter region, where RNA polymerase binds to initiate transcription.

5. **Conclusion**: Therefore, the target for the attachment of the repressor protein produced by the regulator gene is the **operator**.

### Final Answer:
The target for the attachment of the repressor protein produced by the regulator gene is the **operator**.

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