Pivot joint `:-`

Options

A. Axial joint
B. Shoulder joint
C. Hip joint
D. None

Answer

### Step-by-Step Solution:

1. **Understanding the Pivot Joint**: A pivot joint is a type of synovial joint that allows for rotational movement around a single axis. It is characterized by one bone rotating within a ring formed by another bone and a ligament.

2. **Identifying the Options**: The question provides four options:
- a) Axial joint
- b) Shoulder joint
- c) Hip joint
- d) None

3. **Analyzing Each Option**:
- **Axial Joint**: This is indeed a pivot joint. It allows for rotation around an axis, which is the defining characteristic of pivot joints.
- **Shoulder Joint**: This is a ball-and-socket joint, allowing for a wide range of movement but not specifically axial rotation.
- **Hip Joint**: Similar to the shoulder joint, this is also a ball-and-socket joint and does not function as a pivot joint.
- **None**: This option suggests that none of the above are pivot joints, which is incorrect since the axial joint is a pivot joint.

4. **Conclusion**: Based on the analysis, the correct answer is **a) Axial joint**, as it is the only option that describes a pivot joint.