The green scum seen in the freshwater bodies is

Options

A. blue green algae
B. red algae
C. green algae
D. both (a) and (c )

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the green scum that is commonly observed in freshwater bodies. This scum can be indicative of certain types of algae.

2. **Identifying the Types of Algae**: The options provided are:
- A) Blue Green Algae (BGA)
- B) Red Algae
- C) Green Algae
- D) Both A and C (Blue Green Algae and Green Algae)

3. **Analyzing the Characteristics of Algae**:
- **Blue Green Algae (BGA)**: Also known as cyanobacteria, these are photosynthetic microorganisms that can form blooms in nutrient-rich waters, leading to the formation of green scum.
- **Green Algae**: These are also photosynthetic organisms that can contribute to the green coloration in water bodies.
- **Red Algae**: Typically found in marine environments and are not associated with the green scum in freshwater.

4. **Impact on Freshwater Bodies**: The green scum formed by these algae can lead to decreased oxygen levels in the water, which can choke and harm aquatic life.

5. **Conclusion**: Since both Blue Green Algae and Green Algae can contribute to the green scum seen in freshwater bodies, the correct answer is D) Both A and C.

**Final Answer**: The green scum seen in freshwater bodies is both Blue Green Algae and Green Algae (Option D).

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