This is the region of a long bone that articulates with other bones.

Options

A. Diaphysis
B. Epiphysis
C. Metaphysis
D. Periosteum

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the specific region of a long bone that articulates with other bones. This means we are looking for the part of the bone that connects or forms a joint with another bone.

2. **Identifying the Options**: The options provided are:
- Diaphysis
- Epiphysis
- Metaphysis
- Periosteum

3. **Analyzing Each Option**:
- **Diaphysis**: This is the midsection or shaft of the long bone. It does not articulate with other bones, so this option is incorrect.
- **Epiphysis**: This is the end part of the long bone that articulates with other bones at the joints. This is the correct answer.
- **Metaphysis**: This is the region between the diaphysis and epiphysis, which is not the articulating part, so it is incorrect.
- **Periosteum**: This is a dense layer of vascular connective tissue that envelops the bones except at the surfaces of the joints. It does not articulate with other bones, making it incorrect.

4. **Conclusion**: After analyzing all the options, the correct answer is **Epiphysis**, as it is the region of the long bone that articulates with other bones.

**Final Answer**: The region of a long bone that articulates with other bones is called the **Epiphysis**.

---