Assertion : Cultural eutrophication is nutrient enrichment of water bodies due to human activities like passage of sewage, industrial effluents, etc.
Reason : The prime contaminants from sewage and industrial effluents are nitrates and phosphates, which act as plant nutrients and overstimulate the growth of algae.

Answer

To analyze the given assertion and reason, we will break down the statements step by step.

### Step 1: Understand the Assertion
The assertion states that "Cultural eutrophication is nutrient enrichment of water bodies due to human activities like passage of sewage, industrial effluents, etc."

- **Explanation**: Cultural eutrophication refers to the process where water bodies become enriched with nutrients, primarily due to human activities. This includes the discharge of sewage, industrial waste, and runoff from agricultural fields that contain fertilizers.

### Step 2: Understand the Reason
The reason states that "The prime contaminants from sewage and industrial effluents are nitrates and phosphates, which act as plant nutrients and overstimulate the growth of algae."

- **Explanation**: Nitrates and phosphates are indeed the main nutrients found in sewage and industrial effluents. When these nutrients enter water bodies, they promote excessive growth of algae, leading to a phenomenon known as algal bloom.

### Step 3: Evaluate the Truth of the Statements
- **Assertion**: True. Cultural eutrophication is indeed caused by human activities that lead to nutrient enrichment in water bodies.
- **Reason**: True. Nitrates and phosphates are the primary contaminants that contribute to this process by acting as nutrients for algae.

### Step 4: Determine the Relationship Between the Assertion and Reason
- While both the assertion and reason are true, the reason does not directly explain the assertion. The assertion describes the phenomenon of cultural eutrophication, while the reason provides specific details about the contaminants involved.

### Conclusion
Both the assertion and reason are correct, but the reason is not the correct explanation of the assertion.

### Final Answer
Both assertion and reason are correct, but the reason is not the correct explanation of the assertion.

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