Which of the following statements is correct?

Options

A. Excessive use of pesticides pollute the ground water
B. Excessive use of fertilisers purifies the ground water,
C. Aquatic life grows in the presence of excess fertilisers in water
D. Washing away of fertilisers into water bodies is called bleaching

Answer

To determine which statement is correct regarding pollution and its effects, let's analyze each option step by step.

### Step 1: Analyze Option 1
**Statement:** Excessive use of pesticides pollute the groundwater.

- **Explanation:** Pesticides are chemicals used to kill pests. When used excessively, they can run off into the soil and eventually seep into groundwater sources, leading to contamination. This statement is correct.

### Step 2: Analyze Option 2
**Statement:** Excessive use of fertilizers purify the groundwater.

- **Explanation:** Fertilizers contain nutrients that can enhance plant growth. However, when used in excess, they can leach into groundwater, causing pollution rather than purification. This statement is incorrect.

### Step 3: Analyze Option 3
**Statement:** Aquatic life grows in the presence of excess fertilizer in water.

- **Explanation:** While fertilizers can initially promote plant growth, excessive amounts can lead to algal blooms. These blooms consume oxygen in the water, harming aquatic life. Thus, this statement is incorrect.

### Step 4: Analyze Option 4
**Statement:** Washing away of fertilizers into water bodies is called bleaching.

- **Explanation:** Bleaching refers to the process of removing color or stains, typically with chemicals like bleach. The runoff of fertilizers into water bodies is not related to bleaching. Therefore, this statement is incorrect.

### Conclusion
After analyzing all the options, the correct statement is:
**Option 1: Excessive use of pesticides pollute the groundwater.**

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