Joint pains in old people are mostly due to

Options

A. Reduced synovial fluid
B. Overproduction of synovial fluid
C. Formation of extra osteocytes
D. All the above.

Answer

### Step-by-Step Solution:

1. **Understanding Joint Pains**: Joint pains in older individuals are a common issue that can arise from various factors. It's important to identify the primary cause specific to aging.

2. **Role of Synovial Fluid**: Synovial fluid is a viscous liquid found in the cavities of synovial joints (freely movable joints). It serves as a lubricant to reduce friction between the articular cartilage of synovial joints during movement.

3. **Aging and Synovial Fluid Production**: As people age, the production of synovial fluid decreases. This reduction leads to less lubrication in the joints, making movements more difficult and painful.

4. **Impact on Joints**: The knee joint is particularly affected by this decrease in synovial fluid, which can lead to increased friction and wear on the joint surfaces, resulting in pain and discomfort.

5. **Evaluating Other Options**: The question may provide other options regarding the causes of joint pain. However, options such as overproduction of synovial fluid or formation of extra osteocytes (cells involved in bone formation) are incorrect. Osteocytes do not increase in number with age; instead, bone density may decrease.

6. **Conclusion**: Based on the understanding of synovial fluid and its role in joint health, the correct answer to the question is that joint pains in old people are mostly due to the reduced synovial fluid.

### Final Answer:
Joint pains in old people are mostly due to the reduced synovial fluid.

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