Select the correct arrangement of the types of ultraviolet radiations according to the intensity of their effect on human skin

Options

A. `UV-A gt UV-B gt UV-C`
B. `UV-B gt UV-C gt UV-A`
C. `UV-C gt UV-B gt UV-A`
D. `UV-A gt UV-C gt UV-B`

Explanation

To solve the question regarding the correct arrangement of types of ultraviolet (UV) radiation according to their intensity of effect on human skin, we will analyze the three types of UV radiation: UVA, UVB, and UVC.

### Step-by-Step Solution:

1. **Identify the Types of UV Radiation**:
- There are three types of UV radiation: UVA, UVB, and UVC.

2. **Understand the Characteristics of Each Type**:
- **UVA (320-400 nm)**: This type has the longest wavelength and is less intense. It penetrates the skin more deeply but is generally considered less harmful than UVB.
- **UVB (280-320 nm)**: This type has a medium wavelength and is more intense than UVA. It is responsible for causing sunburn and has a significant effect on the skin, including the potential to cause skin cancer.
- **UVC (100-280 nm)**: This type has the shortest wavelength and is the most intense. However, UVC is mostly absorbed by the Earth's atmosphere and does not reach the surface, so it has minimal direct effect on human skin.

3. **Rank the Types Based on Their Intensity of Effect**:
- From the analysis, we can rank them based on their intensity of effect on human skin:
- **1st**: UVB (most harmful)
- **2nd**: UVA (less harmful)
- **3rd**: UVC (not harmful as it is absorbed by the atmosphere)

4. **Select the Correct Option**:
- Based on the ranking, the correct arrangement according to the intensity of their effect on human skin is:
- **UVB > UVA > UVC**
- Therefore, the correct option is **Option B: UVB, UVC, UVA**.

### Final Answer:
**The correct arrangement of the types of ultraviolet radiations according to the intensity of their effect on human skin is Option B: UVB, UVC, UVA.**

---