Excretory structures of rotifers are

Options

A. Green glands
B. Malpighian tubules
C. Flame cells
D. Gills

Answer

### Step-by-Step Solution:

1. **Understanding Rotifers**:
- Rotifers are microscopic aquatic animals that belong to the phylum Rotifera. They are known for their unique feeding habits, primarily consuming dead bacteria, algae, and protozoans.

2. **Identifying Excretory Structures**:
- The question asks about the excretory structures of rotifers. Excretion is a vital process for removing metabolic waste from the body.

3. **Options Analysis**:
- The options provided are:
- A) Green glands
- B) Malpighian tubules
- C) Flame cells
- D) Gills

4. **Evaluating Each Option**:
- **Green Glands**: These are excretory structures found in crustaceans and are not present in rotifers. Therefore, this option is incorrect.
- **Malpighian Tubules**: These are found in insects, such as cockroaches, and are responsible for excretion. This option is also incorrect for rotifers.
- **Flame Cells**: These are specialized excretory cells found in rotifers and also in flatworms (phylum Platyhelminthes). They help in the removal of nitrogenous waste. This option is correct.
- **Gills**: While gills can play a role in excretion (particularly in aquatic animals), they are not the primary excretory structures in rotifers. Thus, this option is incorrect.

5. **Conclusion**:
- The correct answer to the question about the excretory structures of rotifers is **C) Flame cells**.