Assertion. Inflammation of a skeletal joint may immobilize the movements of the joint.
Reason. Uric acid crystals in the joint cavity and ossification of articular cartilage lead to this.

Options

A. If both Assertion and Reason are true and the Reason is correct explanation of the Assertion, then mark a.
B. If both Assertion and Reason are true but the Reason is not the correct explantation of the Assertion, then mark b.
C. If Assertion is true statement but reason is false, then mark c.
D. If both Assertion and Reason are false statements then mark d.

Answer

To solve the assertion and reason question, we will analyze both statements step by step.

### Step 1: Analyze the Assertion
The assertion states: "Inflammation of a skeletal joint may immobilize the movements of the joint."
- Inflammation of joints is commonly referred to as arthritis.
- When a joint is inflamed, it can lead to pain, swelling, and stiffness, which can significantly restrict movement.

### Step 2: Analyze the Reason
The reason states: "Uric acid crystals in the joint cavity and ossification of articular cartilage lead to this."
- Uric acid crystals can accumulate in the joint cavity, particularly in conditions like gout, leading to severe pain and inflammation.
- Ossification refers to the hardening of cartilage, which can also restrict movement in the joint.

### Step 3: Determine the Relationship
- Both the assertion and the reason are correct.
- The reason (the presence of uric acid crystals and ossification) explains why inflammation can lead to immobilization of the joint.

### Conclusion
Both the assertion and the reason are correct, and the reason provides a valid explanation for the assertion. Therefore, the correct answer is that both statements are true, and the reason explains the assertion.

### Final Answer:
Both the assertion and reason are correct, and the reason explains the assertion.

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