Most important causative pollutant is

Options

A. Plastic
B. Glass junk
C. Iron junk
D. Detergents.

Answer

**Step-by-Step Text Solution:**

1. **Identify the Options**: The question presents four options: plastic, glass junk, iron junk, and detergents.

2. **Understanding Detergents**: Among these options, detergents are highlighted as a significant pollutant. They are commonly used in households and industries.

3. **Eutrophication Process**: When detergents are released into water bodies, they introduce chemicals like phosphates and sulfates. Phosphates, in particular, serve as nutrients for algae.

4. **Algae Bloom Formation**: The presence of phosphates leads to rapid growth of algae, resulting in a phenomenon known as "algae bloom." This bloom covers the water surface, blocking sunlight and disrupting the ecosystem.

5. **Oxygen Depletion**: Algae undergo aerobic respiration, consuming dissolved oxygen in the water. This leads to a significant reduction in oxygen levels, making it difficult for aquatic life to survive.

6. **Impact on Aquatic Life**: The depletion of oxygen results in the death of fish and other aquatic organisms, leading to a decline in biodiversity in the affected water body.

7. **Long-term Consequences**: This process is referred to as eutrophication, which can lead to the aging of lakes and other water bodies, eventually rendering them lifeless and turning them into land.

8. **Comparison with Other Pollutants**: While plastic, glass junk, and iron junk are also pollutants, they are non-degradable and do not have the same immediate and severe ecological impact as detergents.

9. **Conclusion**: Based on the understanding of the effects of detergents on aquatic ecosystems, the most important causative pollutant among the given options is detergents.

**Final Answer**: Detergents.

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