The discharge of excessive chemicals from industries, households, etc., into ponds is responsible for which of the following effects?

Options

A. It makes the pond water toxic for algae
B. It increases the level of oxygen in the pond
C. It reduces the temperature of water in the pond
D. It decreases the population of aquatic organisms

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks about the effects of excessive chemical discharge from industries and households into ponds. We need to identify the consequences of this pollution.

2. **Identifying the Effects of Chemical Discharge:**
- When excessive chemicals are discharged into ponds, they can lead to water pollution.
- Water pollution can have several negative effects on the aquatic ecosystem.

3. **Analyzing the Options:**
- **Option A:** "It makes the pond water toxic for algae." - This is a possible effect, as toxic substances can harm algae.
- **Option B:** "It increases the level of oxygen in the pond." - This is incorrect; pollution typically decreases oxygen levels.
- **Option C:** "It reduces the temperature of the water in the pond." - This is also incorrect; pollution can increase water temperature due to various factors.
- **Option D:** "It decreases the population of the aquatic organism." - This is a likely effect, as pollution can lead to a decline in aquatic life due to lower oxygen levels and toxic conditions.

4. **Conclusion:** The most accurate answer is **Option D: It decreases the population of the aquatic organism.** This is because the introduction of excessive chemicals leads to a decline in water quality, which negatively impacts aquatic organisms.

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