Which of the following is formed in nucleolus

Options

A. r RNA
B. t RNA
C. m-RNA
D. DNA

Answer

### Step-by-Step Solution:

1. **Understand the Question**: The question asks which type of RNA is formed in the nucleolus of a cell.

2. **Identify the Options**: The options provided are:
- Ribosomal RNA (rRNA)
- Transfer RNA (tRNA)
- Messenger RNA (mRNA)
- DNA

3. **Recall the Function of the Nucleolus**: The nucleolus is a specialized structure within the nucleus of eukaryotic cells. Its primary function is the synthesis of ribosomal RNA (rRNA) and the assembly of ribosomes.

4. **Analyze Each Option**:
- **Ribosomal RNA (rRNA)**: This is synthesized in the nucleolus and is a key component of ribosomes, which are essential for protein synthesis.
- **Transfer RNA (tRNA)**: This is synthesized in the nucleus but not specifically in the nucleolus; it is then transported to the cytoplasm.
- **Messenger RNA (mRNA)**: This is also synthesized in the nucleus, but like tRNA, it is not produced in the nucleolus.
- **DNA**: This is found in the nucleus but is not synthesized in the nucleolus.

5. **Conclusion**: Based on the analysis, the correct answer is ribosomal RNA (rRNA), as it is specifically formed in the nucleolus.

### Final Answer:
The correct option is **Ribosomal RNA (rRNA)**.

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