The only movable bone of the skull is :

Options

A. Maxilla
B. Ethmoid
C. Mandible
D. Sphenoid

Answer

**Step-by-Step Solution:**

1. **Understanding the Skull Structure**: The skull is composed of various bones that serve to protect the brain and form the structure of the face. It includes both movable and immovable bones.

2. **Identifying the Types of Jaw Bones**: The skull consists of two types of jaw bones: the upper jaw and the lower jaw. The upper jaw, known as the maxilla, is immovable, while the lower jaw is movable.

3. **Examining the Options**: The options provided are:
- Maxilla
- Ethmoid
- Mandible
- Sphenoid

4. **Analyzing Each Option**:
- **Maxilla**: This is the upper jaw bone and is immovable.
- **Ethmoid**: This is a bone located between the nasal cavity and the orbits; it is also immovable.
- **Mandible**: This is the lower jaw bone and is the only movable bone in the skull.
- **Sphenoid**: This is a complex bone located at the base of the skull; it is immovable.

5. **Conclusion**: Based on the analysis, the only movable bone of the skull is the **mandible**.

**Final Answer**: The only movable bone of the skull is the **mandible**.

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