Common indicator organism of water pollution is

Options

A. Lemna paucicostata
B. Eichhornia crassipes
C. Escherichia coli
D. Entamoeba histolytica

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the common indicator organism of water pollution. Indicator organisms are species whose presence in water indicates contamination, particularly from fecal matter.

2. **Identifying the Options**: The options given are Lema, Pococostata, Echornea, Craspies, Escherichia coli, and Entamoeba histolytica.

3. **Analyzing Each Option**:
- **Lema**: Not commonly associated with water pollution.
- **Pococostata**: Not a recognized indicator organism for water pollution.
- **Echornea**: Not known as a common indicator of water pollution.
- **Craspies**: No significant relevance to water pollution.
- **Escherichia coli (E. coli)**: This is a bacterium commonly found in the intestines of humans and animals. Its presence in water indicates fecal contamination, making it a strong indicator of water pollution.
- **Entamoeba histolytica**: This is a protozoan parasite, but it is not a common indicator organism for water pollution.

4. **Conclusion**: Based on the analysis, the common indicator organism of water pollution is **Escherichia coli (E. coli)**. Its presence in water suggests contamination by fecal matter, indicating that the water is unsafe for drinking and may also be uninhabitable for aquatic life.

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