Floating ribs of thoracic cage are

Options

A. 1st to `7^(th)` pair
B. 8th to 9th pair
C. 8th to 10th pair
D. 11th to 12th pair

Answer

To solve the question regarding the floating ribs of the thoracic cage, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Thoracic Cage**:
- The thoracic cage is made up of the sternum and ribs. The sternum consists of three parts: the manubrium, body, and xiphoid process.

2. **Classify the Ribs**:
- Ribs are classified into two main categories: true ribs and false ribs.
- True ribs are the first seven pairs (1st to 7th pair) which attach directly to the sternum.
- False ribs include the 8th to 12th pairs, which do not attach directly to the sternum.

3. **Identify the Types of False Ribs**:
- Among the false ribs, the last two pairs (11th and 12th pairs) are specifically known as floating ribs.
- Floating ribs do not have any anterior attachment to the sternum or to other ribs.

4. **Conclusion**:
- Therefore, the floating ribs of the thoracic cage are the 11th and 12th pairs.

### Final Answer:
The floating ribs of the thoracic cage are the **11th to 12th pair**.

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