Which of the following genes provides attachment site for RNA polymerase?

Options

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

Answer

To determine which gene provides the attachment site for RNA polymerase, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding RNA Polymerase Function**:
- RNA polymerase is an enzyme responsible for synthesizing RNA from a DNA template during the process of transcription.

2. **Identifying the Role of Genes in Transcription**:
- In the context of gene expression, there are specific regions in DNA that play crucial roles. Among these, the promoter region is essential for the initiation of transcription.

3. **Defining the Promoter Region**:
- The promoter is a specific DNA sequence located upstream (before) the structural genes. It serves as the binding site for RNA polymerase, allowing it to initiate transcription.

4. **Distinguishing Between Different Gene Types**:
- While there are various types of genes involved in gene regulation (such as structural genes, regulatory genes, and operator genes), the promoter is specifically the site where RNA polymerase attaches.

5. **Conclusion**:
- Based on the understanding that the promoter gene is the attachment site for RNA polymerase, we can conclude that the correct answer to the question is the "promoter gene."

### Final Answer:
The gene that provides the attachment site for RNA polymerase is the **promoter gene**.

---