Nucleolus is an organelle responsible for the production of

Options

A. carbohydrates
B. messenger RNA
C. lipids
D. ribosomal RNA

Explanation

**Step-by-Step Solution:**

1. **Identify the Organelle**: The question asks about the nucleolus, which is an organelle found within the nucleus of eukaryotic cells.

2. **Understand the Function of Nucleolus**: The primary role of the nucleolus is to produce ribosomal RNA (rRNA). This is crucial because rRNA is a key component of ribosomes, which are essential for protein synthesis.

3. **Clarify the Production Site**: The nucleolus is often referred to as the site of rRNA synthesis. It assembles rRNA with proteins to form the subunits of ribosomes.

4. **Differentiate from Other RNA Types**: While other types of RNA, such as messenger RNA (mRNA), are produced in the nucleus, the nucleolus specifically focuses on rRNA production. Other organelles, like the smooth endoplasmic reticulum, are involved in lipid synthesis, which is unrelated to the function of the nucleolus.

5. **Select the Correct Answer**: Based on the information, the correct answer to the question is that the nucleolus is responsible for the production of ribosomal RNA (rRNA).

**Final Answer**: The nucleolus is an organelle responsible for the production of ribosomal RNA (rRNA).

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