Which one of the following pairs is not correct matched?

Options

A. Production of sulphur - Burning of coal
B. Depletion of ozone - Release of CFCs in the atmosphere
C. Eutrophication - Increase in nitrogen and phosphorus content in aquatic bodies
D. Decrease in BOD of pond water - Increase in global temperature

Answer

To determine which pair is not correctly matched, we will analyze each option provided in the question step by step.

### Step 1: Analyze the first pair - Burning of sulfur
- **Explanation**: The burning of sulfur typically refers to the combustion of sulfur-containing fuels, which can produce sulfur dioxide (SO2). This is a correct match because burning coal, which often contains sulfur, does indeed produce sulfur dioxide.
- **Conclusion**: This pair is correctly matched.

### Step 2: Analyze the second pair - Depletion of ozone
- **Explanation**: Ozone depletion occurs primarily due to chlorofluorocarbons (CFCs) that release chlorine when they are broken down by UV radiation. This chlorine reacts with ozone (O3), leading to its depletion.
- **Conclusion**: This pair is correctly matched.

### Step 3: Analyze the third pair - Eutrophication
- **Explanation**: Eutrophication is characterized by an increase in nutrients, particularly nitrogen and phosphorus, in aquatic ecosystems, leading to excessive growth of algae (like blue-green algae). This can result in decreased oxygen levels in the water, affecting aquatic life.
- **Conclusion**: This pair is correctly matched.

### Step 4: Analyze the fourth pair - Biological oxygen demand and global temperature
- **Explanation**: The biological oxygen demand (BOD) typically increases when organic matter decomposes in water, leading to oxygen depletion. However, the statement suggests that there is a decrease in BOD with an increase in global temperature, which is misleading. Increased global temperatures can lead to higher rates of respiration and decomposition, which would typically increase BOD, not decrease it.
- **Conclusion**: This pair is not correctly matched.

### Final Answer
The pair that is not correctly matched is the one that states "decrease in the biological oxygen demand" with "increase in global temperature."

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