Transcription refers to:

Options

A. Transfer of genetic information of RNA in the form of genetic codon of DNA
B. Transfer of genetic information of DNA in the form of genetic codon of DNA
C. Transfer of genetic information of RNA in the form of genetic codon of mRNA
D. Transfer of genetic information of DNA in the form of genetic codon of mRNA

Answer

To solve the question "Transcription refers to:", we need to analyze the options provided and understand the concept of transcription in molecular biology.

### Step-by-Step Solution:

1. **Understanding Transcription**:
- Transcription is the process by which the information in a segment of DNA is copied into messenger RNA (mRNA). This is the first step in the expression of genes.

2. **Identifying the Source**:
- In transcription, the source of genetic information is DNA. The DNA serves as a template for synthesizing mRNA.

3. **Recognizing the Product**:
- The product of transcription is mRNA, which carries the genetic information from DNA to the ribosome, where proteins are synthesized.

4. **Analyzing the Options**:
- **Option A**: Transfer of genetic information of RNA in the form of genetic codon of DNA.
- This is incorrect because RNA does not transfer information from DNA; rather, DNA is transcribed into RNA.
- **Option B**: Transfer of genetic information of DNA in the form of genetic codon of DNA.
- This is incorrect because it does not mention mRNA, which is the product of transcription.
- **Option C**: Transfer of genetic information of RNA in the form of genetic codon of mRNA.
- This is incorrect because it suggests that RNA transfers information, which is not the case in transcription.
- **Option D**: Transfer of genetic information of DNA in the form of genetic codon of mRNA.
- This is correct because it accurately describes that DNA is transcribed into mRNA, which contains the genetic codons.

5. **Conclusion**:
- Based on the analysis, the correct answer is **Option D**: Transfer of genetic information of DNA in the form of genetic codon of mRNA.