Most of the sponges are marine and remain attached to rock ( sessile ). The frest water sponge is

Options

A. Sycon
B. Spongilla
C. Cliona
D. Euplectella

Answer

To solve the question regarding the freshwater sponge, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Characteristics of Sponges**:
- Most sponges are marine organisms and are typically sessile, meaning they are attached to a substrate like rocks.

2. **Identify the Family of Freshwater Sponges**:
- It is important to note that while most sponges are marine, there is a specific family of sponges that are found in freshwater environments.

3. **Recognize the Family Name**:
- The family that includes freshwater sponges is known as **Spongylidae**.

4. **Identify the Genus**:
- Within the family Spongylidae, the genus that represents the freshwater sponge is **Spongyla**.

5. **Conclusion**:
- Therefore, the freshwater sponge is identified as **Spongyla**.

### Final Answer:
The freshwater sponge is **Spongyla**.

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