Assertion `:-` A chemosensitive area is situated adjacent to the rhythm centre which is highly adjacent to the rhythm centre which is highly sensitive to `CO_(2` and hydrogen ions.
Reason `:-` The role of oxygen in the regulation of respiratory rhythm is quite insignificant .

Options

A. If both Assertion & Reason are True & the Reasonn is a correct explanation of the Assertion .
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.

Answer

To solve the assertion and reason question, we will analyze both statements step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that a chemosensitive area is located adjacent to the rhythm center and is highly sensitive to carbon dioxide (CO₂) and hydrogen ions (H⁺).
- This is true because the chemosensitive area, which includes the medulla oblongata, contains receptors that detect changes in CO₂ and H⁺ levels in the blood. An increase in CO₂ leads to an increase in H⁺ concentration, which decreases blood pH (making it more acidic).

2. **Understanding the Reason**:
- The reason states that the role of oxygen in the regulation of respiratory rhythm is quite insignificant.
- This is also true. While oxygen levels do play a role in respiration, the primary drive for breathing is regulated by CO₂ levels. The chemoreceptors respond primarily to changes in CO₂ and H⁺, making the role of oxygen less significant in this context.

3. **Assessing the Relationship**:
- Both the assertion and the reason are true statements. However, the reason does not explain the assertion. The assertion focuses on the sensitivity to CO₂ and H⁺, while the reason discusses the role of oxygen, which is not directly related to the assertion's focus.

4. **Conclusion**:
- Since both the assertion and reason are true, but the reason does not provide a correct explanation for the assertion, the correct answer is that both are true, but the reason is not the correct explanation of the assertion.

### Final Answer:
**Option B**: Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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