The longest and strongest bone of human body:

Options

A. Humerus
B. Radius - ulna
C. Femur
D. Tibia

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the longest and strongest bone in the human body.

2. **Review the Options**: The options provided are:
- Humerus
- Radius and Ulna
- Femur
- Tibia

3. **Analyze Each Option**:
- **Humerus**: This bone runs from the shoulder to the elbow. It is not the longest or strongest bone.
- **Radius and Ulna**: These bones are located in the forearm, running from the elbow to the wrist. They are not the longest bone.
- **Femur**: This bone is located in the thigh and runs from the hip to the knee. It is known to be the longest and strongest bone in the human body.
- **Tibia**: This bone runs from the knee to the ankle. It is not the longest bone.

4. **Conclusion**: Based on the analysis, the femur is the longest and strongest bone in the human body.

5. **Final Answer**: The correct answer is **Femur**.

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