Mark the correct statement

Options

A. The major contribution in green house gases is of `CH_(4)`
B. Global warming is because of ozone depletion
C. When organic waste enters into a water body its BOD increases
D. All of these

Answer

To solve the question, we need to evaluate each of the given statements and determine which one is correct. Here’s a step-by-step breakdown:

### Step 1: Analyze the First Statement
- **Statement**: The major contribution in greenhouse gases is of methane.
- **Evaluation**: This statement is incorrect. While methane is a significant greenhouse gas, the major contributor to greenhouse gases is carbon dioxide (CO2).

### Step 2: Analyze the Second Statement
- **Statement**: Global warming is because of ozone depletion.
- **Evaluation**: This statement is also incorrect. Global warming is primarily caused by the increase in greenhouse gases like carbon dioxide and methane, not by ozone depletion.

### Step 3: Analyze the Third Statement
- **Statement**: When organic waste enters into the water body, its BOD increases.
- **Evaluation**: This statement is correct. BOD (Biological Oxygen Demand) increases when organic waste is present in water because it leads to a higher demand for oxygen by microorganisms that decompose the organic matter.

### Step 4: Analyze the Fourth Statement
- **Statement**: All of these.
- **Evaluation**: This statement is incorrect because only the third statement is correct, while the first and second statements are wrong.

### Conclusion
The only correct statement is the third one: "When organic waste enters into the water body, its BOD increases."

### Final Answer
The correct statement is: **When organic waste enters into the water body, its BOD increases.**

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