$ Neuron means a nerve cell.
! Neurons are found in the brain.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "Neuron means a nerve cell." This is a true statement. Neurons are indeed specialized cells that are responsible for transmitting information throughout the nervous system.

2. **Identifying Neurons in the Brain:**
- The second part of the assertion states that "Neurons are found in the brain." This is also true. Neurons are present in the brain as well as in the spinal cord and throughout the nervous system.

3. **Explaining the Role of Neurons:**
- Neurons serve as the structural and functional units of the nervous system. They are specialized for conducting electrical impulses, which is essential for communication within the nervous system.

4. **Evaluating the Relationship Between the Two Statements:**
- While both parts of the assertion are correct, the second part does not serve as a correct explanation for the first part. The fact that neurons are found in the brain does not explain why they are referred to as nerve cells.

5. **Conclusion:**
- Therefore, the assertion is correct, but the reason provided does not adequately explain the assertion.

**Final Answer:**
- The assertion is true: Neurons are indeed nerve cells, and they are found in the brain. However, the reason given (that neurons are found in the brain) is not a correct explanation of the assertion.

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