High amount of Escherichia coli in water indicates

Options

A. Hardness of water
B. Industrial pollution
C. Sewage pollution
D. Pollution due to electromagnetic radiations

Answer

**Step-by-Step Solution:**

1. **Understanding E. coli**: Escherichia coli, commonly known as E. coli, is a type of bacteria that is normally found in the intestines of humans and animals.

2. **Source of E. coli**: E. coli is often present in feces and waste. Therefore, its presence in water can indicate contamination from these sources.

3. **Indicator of Pollution**: High levels of E. coli in water are used as an indicator of water quality. It suggests that the water may be contaminated with sewage or animal waste.

4. **Analyzing the Options**:
- **Option 1: Hardness of water** - This is not related to E. coli levels.
- **Option 2: Industrial pollution** - While industrial pollution can affect water quality, it is not specifically indicated by E. coli.
- **Option 3: Sewage pollution** - This is directly related to the presence of E. coli, as it indicates contamination from sewage or animal waste.
- **Option 4: Pollution due to electromagnetic radiation** - This does not relate to biological contamination and thus is not indicated by E. coli.

5. **Conclusion**: Based on the understanding that E. coli is a strong indicator of sewage and animal waste contamination, the correct answer is **Option 3: sewage pollution**.

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