Environment has been negatively affected by an increase in industrialization. Waste material from various industries is dumped into rivers or lakes. As a result, rivers and lakes get polluted. Which of the following occurrences is not a result of water pollution?

Options

A. Water borne diseases
B. Breeding of mosquitoes
C. Reduction in potable water
D. Decrease in fish population

Answer

To solve the question regarding the effects of water pollution, we need to analyze the options provided and identify which occurrence is not a result of water pollution. Here’s a step-by-step solution:

### Step 1: Understand Water Pollution
Water pollution occurs when harmful substances contaminate water bodies such as rivers and lakes. This can lead to various negative effects on the environment and living organisms.

### Step 2: Identify Possible Effects of Water Pollution
Common effects of water pollution include:
- Water-borne diseases (caused by pathogens in contaminated water)
- Decrease in fish population (due to toxic substances affecting aquatic life)
- Reduction in potable (drinkable) water supply (as pollution makes water unsafe for consumption)
- Breeding of mosquitoes (which can occur in stagnant water, whether polluted or not)

### Step 3: Analyze Each Option
1. **Water-borne diseases**: This is a direct result of water pollution as contaminated water can carry harmful pathogens.
2. **Breeding of mosquitoes**: Mosquitoes can breed in stagnant water, which does not necessarily have to be polluted. They can breed in clean water as well.
3. **Reduction in potable water**: This is a consequence of water pollution since polluted water is often unsafe for drinking.
4. **Decrease in fish population**: This is also a result of water pollution, as toxic substances can harm aquatic life.

### Step 4: Determine the Correct Answer
Among the options, the breeding of mosquitoes is the occurrence that is not directly caused by water pollution, as mosquitoes can breed in both polluted and clean stagnant water. Therefore, the correct answer is the breeding of mosquitoes.

### Final Answer
The occurrence that is not a result of water pollution is **breeding of mosquitoes**.

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