Which of the following is/are not used as diagnostic tool in medicine?

Options

A. X-ray
B. `gamma`-ray
C. Ultrasonic wave
D. None of these

Answer

To solve the question of which of the following is/are not used as a diagnostic tool in medicine, we will analyze each option provided.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are:
- Option 1: X-ray
- Option 2: Gamma rays
- Option 3: Ultrasonic waves
- Option 4: None of these

2. **Analyze Option 1 - X-ray**:
- X-rays are widely used in medicine for diagnostic purposes. They help in viewing the structure of bones and joints.
- **Conclusion**: X-rays are used as a diagnostic tool.

3. **Analyze Option 2 - Gamma rays**:
- Gamma rays have very high energy and penetrating power. While they are used in certain treatments (like cancer therapy), they are not typically used as a diagnostic tool due to their potential to cause damage to human cells and tissues.
- **Conclusion**: Gamma rays are not used as a diagnostic tool in medicine.

4. **Analyze Option 3 - Ultrasonic waves**:
- Ultrasonic waves are commonly used in medical imaging, particularly in ultrasound scans to view organs and tissues inside the human body.
- **Conclusion**: Ultrasonic waves are used as a diagnostic tool.

5. **Analyze Option 4 - None of these**:
- Since we have identified that gamma rays are not used as a diagnostic tool, this option cannot be correct.

6. **Final Conclusion**:
- The only option that is not used as a diagnostic tool in medicine is **Option 2: Gamma rays**.

### Final Answer:
**Option 2: Gamma rays** are not used as a diagnostic tool in medicine.

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