Knee joint is the ball and socket joint.

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Joint Types**: First, we need to understand the different types of joints in the human body. The two types mentioned are ball and socket joints and hinge joints.

2. **Defining the Knee Joint**: The knee joint is often mistakenly referred to as a ball and socket joint. However, it is important to clarify what type of joint it actually is.

3. **Identifying the Knee Joint's Movement**: The knee joint allows for movement primarily in one direction, similar to how a door opens and closes. This type of movement is characteristic of a hinge joint.

4. **Comparing with Ball and Socket Joints**: In contrast, ball and socket joints, like the shoulder joint, allow for a wider range of motion, including 360-degree rotation.

5. **Conclusion**: Based on the movement characteristics, we can conclude that the statement "Knee joint is the ball and socket joint" is false. The knee joint is actually a hinge joint.

6. **Final Statement**: Therefore, we write "false" for the statement regarding the knee joint being a ball and socket joint.

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