During transcription, the site of DNA molecule at which RNA polymerase binds is called

Options

A. promoter
B. regulator
C. receptor
D. enhancer

Explanation

**Step-by-Step Solution:**

1. **Understanding Transcription**: Transcription is the process by which RNA is synthesized from a DNA template. This is a crucial step in gene expression.

2. **Identifying the Role of RNA Polymerase**: RNA polymerase is the enzyme responsible for synthesizing RNA. It binds to specific regions of the DNA to initiate transcription.

3. **Locating the Binding Site**: The specific site on the DNA molecule where RNA polymerase binds is essential for the initiation of transcription. This site is known as the promoter.

4. **Defining the Promoter**: The promoter is a region of DNA that contains specific sequences recognized by RNA polymerase. It is located upstream of the gene that is to be transcribed.

5. **Function of the Promoter**: The promoter not only serves as the binding site for RNA polymerase but also determines which of the two DNA strands will be transcribed into RNA.

6. **Conclusion**: Therefore, during transcription, the site of the DNA molecule at which RNA polymerase binds is called the promoter.

**Final Answer**: The correct answer is **promoter**.

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