Match the column
`{:(,"Column I",,"Column II"),(a.,"Ozone thickness",(i),"UV-rays"),(b.,"CFC",(ii),"Refrigerator"),(c.,"EI Nino effect",(iii),"Temperature increase"),(d.,"Skin cancer",(iv),"Dobson unit"):}`

Options

A. a(i), b(ii), c(iii), d(iv)
B. a(ii), b(iii), c(iv), d(i)
C. a (iv), b(ii), c(iii), d(i)
D. a(iii), b(iv), c(ii), d(i)

Answer

To solve the matching question, we need to connect the items in Column I with the appropriate items in Column II based on their relationships. Let's go through each item step by step.

### Step-by-Step Solution:

1. **Ozone Thickness**:
- Ozone thickness refers to the amount of ozone present in the atmosphere, which is measured using a unit called the **Dobson unit**.
- **Match**: Ozone thickness (a) → Dobson unit (iv)

2. **CFC (Chlorofluorocarbons)**:
- CFCs are chemicals that are primarily released from products like **refrigerators** and are known for depleting the ozone layer.
- **Match**: CFC (b) → Refrigerator (ii)

3. **El Nino Effect**:
- The El Nino effect is associated with drastic changes in climate and is primarily caused by the **increase in temperature** of the Pacific Ocean.
- **Match**: El Nino effect (c) → Temperature increase (iii)

4. **Skin Cancer**:
- Skin cancer is primarily caused by the harmful effects of **UV rays**, which penetrate the atmosphere due to ozone depletion.
- **Match**: Skin cancer (d) → UV rays (i)

### Final Matches:
- a → iv (Ozone thickness → Dobson unit)
- b → ii (CFC → Refrigerator)
- c → iii (El Nino effect → Temperature increase)
- d → i (Skin cancer → UV rays)

### Summary of Matches:
- (a) Ozone thickness → (iv) Dobson unit
- (b) CFC → (ii) Refrigerator
- (c) El Nino effect → (iii) Temperature increase
- (d) Skin cancer → (i) UV rays

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