Which statement is wrong about water pollution ?

Options

A. The government of India has passed the water (prevention & control of pollution) Act in 1978 to safeguard water
B. Water pollution level is measured in terms of BOD.
C. Presence of large amount of nutrients in water bodies also causes excessive growth of planktonic (free floating) algae.
D. Eichhornia is world's most problematic aquatic weed.

Answer

To determine which statement is wrong about water pollution, we can analyze the provided statements one by one.

### Step-by-Step Solution:

1. **Identify the Statements**:
We need to look at the statements provided in the question regarding water pollution.

2. **Evaluate the First Statement**:
The first statement claims that the Water (Prevention and Control of Pollution) Act was passed in 1978. According to the video transcript, this statement is incorrect; the Act was actually passed in 1974. Therefore, this statement is wrong.

3. **Evaluate the Second Statement**:
The second statement mentions that pollution level norms are measured in terms of BOD (Biochemical Oxygen Demand). The transcript confirms that this statement is correct, as BOD measures the amount of oxygen required by microbes to decompose organic matter in water.

4. **Evaluate the Third Statement**:
The third statement discusses the presence of large amounts of nutrients in water bodies leading to algal blooms. The transcript supports this statement, explaining how excess fertilizers lead to nutrient overload and subsequently algal blooms, which deplete oxygen in the water.

5. **Evaluate the Fourth Statement**:
The fourth statement refers to Aishwarya (water hyacinth) being the world's most problematic aquatic weed. The transcript agrees with this statement, highlighting its rapid propagation and negative impact on aquatic life.

6. **Conclusion**:
After evaluating all the statements, we find that the first statement is the only incorrect one. Therefore, the answer to the question is that the first statement is wrong about water pollution.

### Final Answer:
The wrong statement about water pollution is that the Water (Prevention and Control of Pollution) Act was passed in 1978; it was actually passed in 1974.

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