The main cause for abundant coliform bacteria in the river Ganga is

Options

A. disposal of unburnt corpses into water.
B. discharge of effluents from electroplating industries.
C. washing of clothes.
D. immersion of ashes.

Explanation

**Step-by-Step Solution:**

1. **Understanding Coliform Bacteria**: Coliform bacteria are a group of bacteria commonly found in the environment, including in the feces of warm-blooded animals. Their presence in water indicates potential contamination by fecal matter.

2. **Identifying the Source of Contamination**: The question asks for the main cause of the presence of abundant coliform bacteria in the river Ganga. We need to look at the options provided and determine which one is most likely to introduce fecal bacteria into the river.

3. **Analyzing the Options**:
- **A. Disposal of unburnt corpses into water**: This option suggests that human remains, which may carry coliform bacteria, are disposed of in the river.
- **B. Discharge of effluents**: This could also introduce bacteria, but it depends on the nature of the effluents.
- **C. Washing of cloth**: This is less likely to introduce significant levels of coliform bacteria.
- **D. Immersion of ashes**: Ashes do not carry bacteria and are unlikely to be a source.

4. **Conclusion**: Among the options, the disposal of unburnt corpses (Option A) is the most direct source of coliform bacteria in the river Ganga, as human remains can introduce fecal bacteria into the water.

5. **Final Answer**: The main cause for abundant coliform bacteria in the river Ganga is **A. Disposal of unburnt corpses into water**.

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