Knee joint and elbow joints are examles of

Options

A. saddle joint
B. ball and Socket joint
C. pivot joint
D. hinge joint

Answer

### Step-by-Step Solution:

1. **Understanding Joints**: Joints are the points where two bones meet and allow for movement. They play a crucial role in the skeletal system by providing flexibility and support.

2. **Types of Joints**: There are several types of joints in the human body, each allowing for different types of movement. The main types include:
- Ball and Socket Joints
- Hinge Joints
- Saddle Joints
- Pivot Joints

3. **Identifying the Joint Types**:
- **Ball and Socket Joint**: Allows for a wide range of movement in multiple directions (e.g., shoulder joint).
- **Hinge Joint**: Allows movement primarily in one direction (like a door). Examples include the knee joint and elbow joint.

4. **Specific Examples**:
- The **knee joint** is a hinge joint that allows for flexion and extension.
- The **elbow joint** is also a hinge joint, permitting similar movements.

5. **Conclusion**: Therefore, both the knee joint and the elbow joint are classified as **hinge joints**.

### Final Answer:
Knee joint and elbow joints are examples of **hinge joints**.

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