Bloom occurs in-

Options

A. Oligotrophic lake
B. Eutrophic lake
C. Fast flowing river
D. Rain water

Answer

**Step-by-Step Solution:**

1. **Understand the Concept of Bloom:**
- Bloom refers to the excessive growth of algae in a water body, which can lead to various ecological issues.

2. **Evaluate the Options:**
- The question provides four options: oligotropic lake, eutropic lake, fast flowing river, and rainwater.

3. **Analyze Each Option:**
- **Oligotropic Lake:**
- These lakes have low nutrient levels, which means they do not support the excessive growth of algae. Therefore, this option is incorrect.
- **Eutropic Lake:**
- Eutrophic lakes are characterized by high nutrient levels, particularly nitrogen and phosphorus. This nutrient richness promotes the growth of algae, leading to blooms. Thus, this option is likely correct.
- **Fast Flowing River:**
- Fast flowing rivers typically do not allow for nutrient accumulation in one area, making it unlikely for blooms to occur. This option is also incorrect.
- **Rainwater:**
- Rainwater does not provide a suitable environment for algae blooms as it lacks the necessary nutrients in significant quantities. Hence, this option is incorrect.

4. **Conclusion:**
- Based on the analysis, the correct answer is **Eutropic Lake**, as it is the environment where blooms are most likely to occur due to the high nutrient levels that promote excessive algae growth.

**Final Answer: Eutropic Lake (Option B)**

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