Vertebro-arterial canal occurs in

Options

A. Cervical vertebrae
B. Lumbar vertebrae
C. Thoracic vertebrae
D. Sacral vertebrae.

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks where the vertebro-arterial canal occurs. This requires knowledge of vertebral anatomy and the specific functions of different vertebrae.

2. **Identifying the Options**: The options provided are:
- Cervical vertebrae
- Lumbar vertebrae
- Thoracic vertebrae
- Sacral vertebrae

3. **Analyzing Each Option**:
- **Cervical Vertebrae**: These are the vertebrae located in the neck region, directly below the skull. There are seven cervical vertebrae (C1 to C7).
- **Lumbar Vertebrae**: These are located in the lower back region and do not contain the vertebro-arterial canal.
- **Thoracic Vertebrae**: These are located in the upper and mid-back region and are also not associated with the vertebro-arterial canal.
- **Sacral Vertebrae**: These are fused vertebrae located at the base of the spine and do not contain the vertebro-arterial canal.

4. **Identifying the Correct Answer**: The vertebro-arterial canal is specifically found in the cervical vertebrae. This canal is important as it provides blood supply to critical areas such as the upper spinal cord, brain stem, cerebellum, and the posterior part of the brain.

5. **Conclusion**: Therefore, the correct answer is **Cervical Vertebrae**.

### Final Answer:
The vertebro-arterial canal occurs in **Cervical Vertebrae**.

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