The Kyoto Protocol specifies regulations on the emission of greenhouse gases. It defines a term Known as ''Carbon-Credits''. The following statements pertain to Carbon- Credits.
I. The mandatory limit of Carbon- Credit for each country is directly proportional to its size and pollution.
II. One Carbon-Credit defines the emission of one ton of carbon dioxide or equivalent gases responsible for green house effect.
III. Carbon-Credits are exchangeable among countries/industries.
IV. An industry emitting higher than prescribed limit can do so by purchasing Carbon-Credits.

Options

A. (I) and (II) only
B. (II) and (IV) only
C. (II), (III) and (IV) only
D. (I), (II) and (IV) only

Answer

To determine which statements about Carbon-Credits are correct, we will analyze each statement one by one based on the information provided in the Kyoto Protocol and the concept of Carbon-Credits.

### Step-by-Step Solution:

1. **Statement I: The mandatory limit of Carbon-Credit for each country is directly proportional to its size and pollution.**
- **Analysis:** This statement is correct. The allocation of carbon credits is often based on a country's size (population and economic activity) and its historical emissions. Larger and more industrialized countries typically have higher limits due to their greater contribution to greenhouse gas emissions.

2. **Statement II: One Carbon-Credit defines the emission of one ton of carbon dioxide or equivalent gases responsible for greenhouse effect.**
- **Analysis:** This statement is also correct. One carbon credit indeed represents the right to emit one ton of carbon dioxide or an equivalent amount of other greenhouse gases. This is a fundamental aspect of how carbon credits function.

3. **Statement III: Carbon-Credits are exchangeable among countries/industries.**
- **Analysis:** This statement is correct as well. Carbon credits can be traded between countries and industries, allowing those who have reduced their emissions to sell their excess credits to those who need to emit more.

4. **Statement IV: An industry emitting higher than prescribed limit can do so by purchasing Carbon-Credits.**
- **Analysis:** This statement is correct. Industries that exceed their emission limits can purchase carbon credits from others who have not used their full allowance, thus allowing them to legally emit more greenhouse gases.

### Conclusion:
Based on the analysis of each statement:
- **Correct Statements:** I, II, III, and IV are all correct.
- Therefore, the answer is **D (All of the above statements are correct).**