Which of the following is/are the harmful effect(s) of UV radiation?
It causes mutation in the cell.
UV radiation leads to ageing of skin.
It kills many phytoplanktons.
It causes global warming.

Options

A. I and II correct, III and IV are incorrect
B. I,II and III are correct, IV is incorrect
C. II and IV are correct
D. All are correct

Answer

To determine the harmful effects of UV radiation, let's analyze each statement one by one:

1. **It causes mutation in the cell.**
- UV radiation can indeed cause mutations in DNA. This is because UV rays can damage the genetic material in cells, leading to errors during DNA replication. Such mutations can result in skin cancer and other health issues.
- **Conclusion**: This statement is **correct**.

2. **UV radiation leads to aging of skin.**
- UV radiation is known to accelerate skin aging. It can cause damage to collagen and elastin fibers in the skin, leading to wrinkles, loss of elasticity, and other signs of aging.
- **Conclusion**: This statement is **correct**.

3. **It kills many phytoplanktons.**
- Phytoplanktons are microscopic organisms that form the basis of the aquatic food web. UV radiation can be harmful to these organisms, leading to their death or reduced populations, which can disrupt aquatic ecosystems.
- **Conclusion**: This statement is **correct**.

4. **It causes global warming.**
- Global warming is primarily caused by greenhouse gases like carbon dioxide and methane, not by UV radiation. UV radiation does not contribute to the warming of the Earth's atmosphere.
- **Conclusion**: This statement is **incorrect**.

**Final Assessment**: The harmful effects of UV radiation include causing mutations in cells (1), leading to skin aging (2), and killing phytoplanktons (3). However, it does not cause global warming (4). Therefore, the correct answer is that statements 1, 2, and 3 are correct, while statement 4 is incorrect.

### Summary of the Correct Statements:
- **Correct Effects**: 1 (mutation), 2 (skin aging), 3 (kills phytoplanktons)
- **Incorrect Effect**: 4 (does not cause global warming)