Which of the following connects a bone to a bone?

Options

A. Cartilage
B. Ligament
C. Tendon
D. Interstitial fluid

Explanation

To answer the question "Which of the following connects a bone to a bone?" we will analyze each of the provided options step by step.

### Step-by-Step Solution:

1. **Understand the Options**: The options given are cartilage, ligament, tendon, and interstitial fluid. We need to determine which of these connects a bone to another bone.

2. **Analyze Cartilage**:
- Cartilage is a type of connective tissue that serves as a protective padding at the ends of long bones and at joints.
- It provides cushioning and support but does not connect bones to each other.
- **Conclusion**: Cartilage does not connect a bone to a bone.

3. **Analyze Ligament**:
- Ligaments are also connective tissues that connect bones to other bones.
- They contain collagen fibers that provide strength and flexibility, allowing for stability in joints.
- **Conclusion**: Ligaments are responsible for connecting one bone to another bone.

4. **Analyze Tendon**:
- Tendons are connective tissues that connect muscles to bones.
- Like ligaments, they also contain collagen fibers, but their primary function is to transmit the force from muscles to bones, not to connect bones to each other.
- **Conclusion**: Tendons do not connect a bone to a bone.

5. **Analyze Interstitial Fluid**:
- Interstitial fluid is a non-cellular fluid found between cells and blood vessels.
- Its role is to provide nutrients and support to cells, but it does not have a structural role in connecting bones.
- **Conclusion**: Interstitial fluid does not connect a bone to a bone.

6. **Final Conclusion**:
- Based on the analysis, the only option that connects a bone to a bone is **ligament**.

### Final Answer:
**Ligament** connects a bone to a bone.

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