Which one of the following is not a synovial joint

Options

A. Ball and socket joint
B. Pivot joint
C. Structures forming the cranium
D. Hinge joint.

Answer

To determine which one of the following is not a synovial joint, we will analyze the options provided. Synovial joints are characterized by a fluid-filled joint cavity, allowing for a wide range of motion. Common types of synovial joints include ball and socket joints, hinge joints, and pivot joints.

**Step-by-Step Solution:**

1. **Identify the Types of Joints:**
- Synovial joints include:
- Ball and Socket Joint (e.g., shoulder joint between humerus and scapula)
- Hinge Joint (e.g., elbow and knee joints)
- Pivot Joint (e.g., joint between atlas and axis in the neck)

2. **Analyze the Options:**
- Look at the options provided in the question. We need to identify which one does not belong to the synovial joint category.
- One of the options is "structures forming the cranium."

3. **Determine the Nature of the Cranium Joint:**
- The structures forming the cranium (the skull) are connected by fibrous joints, which do not have a joint cavity and are immovable. These are known as sutures.

4. **Conclusion:**
- Since the structures forming the cranium are fibrous joints and not synovial joints, the correct answer is "structures forming the cranium."

**Final Answer:**
The structures forming the cranium are not a synovial joint.

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