In 1831, Robert Brown discovered

Options

A. Cell
B. Dictyosome
C. Nucleus
D. Nucleolus

Answer

**Step-by-Step Solution:**

1. **Identify the Scientist and Year**: The question asks about a discovery made by Robert Brown in the year 1831.

2. **Understand the Context**: Robert Brown was a botanist who made significant contributions to cell biology. His work involved observing plant cells under a microscope.

3. **Recall the Discovery**: During his observations, Robert Brown discovered a specific structure within the cell. This structure is known as the nucleus.

4. **Define the Nucleus**: The nucleus is a membrane-bound organelle that contains the cell's genetic material (DNA). It plays a crucial role in processes such as DNA replication and protein synthesis.

5. **Select the Correct Answer**: Based on the information provided, the correct answer to the question is option C: nucleus.

**Final Answer**: C. Nucleus

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