Trachea is a straight tube extending up to the mid-thoracic cavity, which divides at the level of

Options

A. Second cervical vertebra
B. Fifth cervical vertebra
C. Fifth thoracic vertebra
D. Fifth lumbar vertebra.

Answer

**Step-by-Step Solution:**

1. **Understanding the Trachea**: The trachea, also known as the windpipe, is a straight tube that conducts air from the throat to the lungs. It is an essential part of the respiratory system.

2. **Location of the Trachea**: The trachea extends down into the thoracic cavity, which is the chest area where the lungs are located. It is important to note that the trachea remains a single structure until it reaches a certain point in the thoracic cavity.

3. **Bifurcation of the Trachea**: The trachea bifurcates, or divides, into two primary bronchi. This division is necessary for air to be distributed to both lungs.

4. **Identifying the Division Level**: The question asks for the specific level at which the trachea divides. The trachea typically bifurcates at the level of the 5th thoracic vertebra (T5) in the mid-thoracic cavity.

5. **Eliminating Incorrect Options**:
- Cervical vertebrae are located in the neck, so the trachea does not bifurcate there.
- Lumbar vertebrae are located in the lower back, which is also incorrect for the bifurcation of the trachea.
- The correct option is therefore at the level of the 5th thoracic vertebra.

6. **Conclusion**: The trachea divides into the primary bronchi at the level of the 5th thoracic vertebra, making option C the correct answer.

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