Assertion : Tracheae, primary, secondary and tertiary bronchi are supported by incomplete carilaginous rings.
Reason : These rings of carilage make the wall non-collapsible.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true and reason is not the correct explanation of assertion
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that the trachea, primary, secondary, and tertiary bronchi are supported by incomplete cartilaginous rings.
- The trachea is the windpipe that connects the larynx to the bronchi, and it does indeed have these cartilaginous rings.

2. **Understanding the Reason**: The reason provided is that these rings of cartilage make the wall non-collapsible.
- The cartilaginous rings prevent the trachea and bronchi from collapsing, ensuring that air can continuously flow to and from the lungs.

3. **Analyzing the Structure**: The trachea and bronchi are lined with these incomplete rings of cartilage, which maintain their structure during breathing.
- The incomplete nature of the rings allows flexibility while still providing support.

4. **Connecting Assertion and Reason**: The assertion is true because the trachea and bronchi are indeed supported by these rings. The reason is also true because the rings prevent collapse, which is essential for maintaining an open airway.
- Therefore, the reason correctly explains why the assertion is true.

5. **Conclusion**: Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

**Final Answer**: Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

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