Synovial fluid is secreted by `:`

Options

A. Blood
B. Cartilage
C. Bone
D. Synovial membrane

Answer

To answer the question "Synovial fluid is secreted by:", follow these steps:

### Step-by-Step Solution:

1. **Understand the Context**: Recognize that synovial fluid is associated with joints in the human body, specifically synovial joints, which are a type of joint that allows for a wide range of motion.

2. **Identify the Components**: Know that synovial joints consist of two bones that are connected and have a space between them filled with synovial fluid.

3. **Locate the Source of Synovial Fluid**: The synovial fluid is not produced by the bones or cartilage directly. Instead, it is secreted by a specific membrane that lines the joint.

4. **Identify the Correct Membrane**: The membrane responsible for secreting synovial fluid is called the **synovial membrane**. This membrane is found within the joint capsule and is crucial for joint lubrication.

5. **Conclusion**: Based on the information gathered, the correct answer to the question is that synovial fluid is secreted by the **synovial membrane**.

### Final Answer:
Synovial fluid is secreted by the **synovial membrane**.

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