Select the mismatched pairs w.r.t. relative contribution of various green house gases to totral global warming: (a) CFCs - 20% (b) `N_2O`-6% © Carbon dioxide - 60% (d) Methane - 14%

Options

A. (a) and (C)
B. (b) & (c)
C. (b) & (d)
D. (a) &(d)

Answer

To solve the question regarding the mismatched pairs of greenhouse gases and their contributions to global warming, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Greenhouse Gases**:
- Greenhouse gases (GHGs) are responsible for trapping heat in the atmosphere, contributing to the greenhouse effect and global warming.

2. **Analyzing Each Option**:
- **(a) CFCs - 20%**:
- CFCs (Chlorofluorocarbons) are known to contribute to global warming, but their actual contribution is around 14%, not 20%.
- **Conclusion**: This pair is mismatched.

- **(b) N₂O - 6%**:
- Nitrous oxide (N₂O) contributes approximately 6% to global warming.
- **Conclusion**: This pair is correctly matched.

- **(c) Carbon dioxide - 60%**:
- Carbon dioxide (CO₂) is the most significant greenhouse gas, contributing about 60% to global warming.
- **Conclusion**: This pair is correctly matched.

- **(d) Methane - 14%**:
- Methane (CH₄) contributes about 20% to global warming, not 14%.
- **Conclusion**: This pair is mismatched.

3. **Identifying Mismatched Pairs**:
- From the analysis, we find that options (a) CFCs - 20% and (d) Methane - 14% are mismatched.

4. **Final Answer**:
- The mismatched pairs with respect to the relative contribution of various greenhouse gases to total global warming are:
- (a) CFCs - 20%
- (d) Methane - 14%