The joint that allows only back and forth movement is present in

Options

A. ribs
B. knees
C. hips
D. wrist

Answer

**Step-by-Step Solution:**

1. **Understanding Joint Types**: First, we need to understand the different types of joints in the human body. Joints can be classified based on the movement they allow.

2. **Identifying the Hinge Joint**: The joint that allows only back and forth movement is known as a hinge joint. This type of joint functions similarly to a door hinge, allowing motion in one direction.

3. **Examples of Hinge Joints**: The most common examples of hinge joints in the human body are the knee and the elbow. Both of these joints allow movement primarily in one plane.

4. **Evaluating the Options**:
- **Ribs**: These are immovable joints and do not allow movement.
- **Knee**: The knee is indeed a hinge joint and allows for back and forth movement.
- **Hips**: The hip joint is a ball-and-socket joint, allowing for a wider range of motion.
- **Wrist**: The wrist is a gliding joint, which allows for sliding movements.

5. **Conclusion**: Based on the evaluation, the joint that allows only back and forth movement is the knee joint.

**Final Answer**: The joint that allows only back and forth movement is present in the **knee**.

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