Physical carcinogens are

Options

A. UV-rays
B. X-rays
C. Y-rays
D. all of these

Answer

### Step-by-Step Solution:

1. **Definition of Carcinogens**: Begin by understanding what carcinogens are. Carcinogens are agents that have the ability to cause cancer in living tissues.

2. **Types of Carcinogens**: Recognize that carcinogens can be classified into two main categories: physical carcinogens and chemical carcinogens.

3. **Identifying Physical Carcinogens**: Focus on physical carcinogens. These are typically forms of radiation that can lead to cancer.

4. **Examples of Physical Carcinogens**: The primary examples of physical carcinogens include:
- **Ultraviolet (UV) Rays**: These rays are emitted by the sun and can damage the DNA in skin cells, leading to skin cancer.
- **X-rays**: These are a form of ionizing radiation used in medical imaging that can also cause cellular damage and increase cancer risk.
- **Gamma Rays**: Similar to X-rays, gamma rays are high-energy radiation that can penetrate tissues and cause DNA damage, which may lead to cancer.

5. **Conclusion**: Therefore, physical carcinogens include UV rays, X-rays, and gamma rays, all of which are forms of ionizing radiation that can lead to cancer.

### Final Answer:
Physical carcinogens are agents such as UV rays, X-rays, and gamma rays that can cause cancer through ionizing radiation.

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