Sacro-iliac joint is `:-`

Options

A. Movable
B. Immovable
C. Imperfect
D. None

Answer

**Step-by-Step Solution:**

1. **Understanding the Sacroiliac Joint**: The sacroiliac joint is a joint that connects the sacrum (a triangular bone at the base of the spine) to the iliac bones (part of the pelvis).

2. **Identifying the Bones Involved**: The sacrum is located at the lower end of the vertebral column, while the iliac bones form the sides of the pelvis. The sacroiliac joint is formed where these two bones meet.

3. **Function of the Sacroiliac Joint**: The primary function of the sacroiliac joint is to transfer forces from the upper body to the lower body. This means it helps in distributing weight and providing stability when standing, walking, or moving.

4. **Mobility of the Sacroiliac Joint**: The sacroiliac joint is characterized by its stability and limited movement. It is designed to be strong and not highly mobile, which is essential for its role in supporting the upper body's weight.

5. **Choosing the Correct Answer**: Given the options (movable, immovable, imperfect, none), the correct answer is that the sacroiliac joint is **immovable**. This means it does not allow for significant movement, aligning with its function of providing stability.

**Final Answer**: The sacroiliac joint is **immovable**.

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