Ribs are attached to

Options

A. scapula
B. sternum
C. clavicle
D. ilium

Explanation

### Step-by-Step Solution:

1. **Understanding the Structure**: Ribs are part of the thoracic cage, which protects vital organs in the chest, such as the heart and lungs.

2. **Counting the Ribs**: There are a total of 12 pairs of ribs in the human body, making a total of 24 ribs.

3. **Attachment Points**:
- **Posterior Attachment**: Ribs are attached to the vertebrae at the back (posteriorly). This means that each rib connects to a corresponding thoracic vertebra.
- **Anterior Attachment**: Ribs are also attached to the sternum at the front (anteriorly).

4. **Connection via Costal Cartilages**: The connection between the ribs and the sternum is facilitated by structures known as costal cartilages. These cartilages are flexible and allow for the expansion and contraction of the rib cage during breathing.

5. **Identifying the Correct Answer**: Given the options, the ribs are primarily attached to the sternum via costal cartilages. Therefore, the correct answer to the question "Ribs are attached to" is the **sternum**.

### Final Answer:
The ribs are attached to the **sternum**.

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