Water enters the body of sponges through

Options

A. Osculum
B. Hypostome
C. Muscular pharynx
D. Ostia

Explanation

To answer the question "Water enters the body of sponges through," we will analyze the options provided and identify the correct one step by step.

### Step-by-Step Solution:

1. **Understanding Sponges**:
- Sponges belong to the phylum Porifera, which is characterized by the presence of numerous pores throughout their body. These pores are essential for their feeding and respiration.

2. **Identifying the Options**:
- The options given are:
- A) Osculum
- B) Hypostome
- C) Muscular pharynx
- D) Ostea

3. **Analyzing Each Option**:
- **Osculum**: This is the large opening at the top of the sponge through which water exits. It does not allow water to enter the sponge.
- **Hypostome**: This term refers to a mouth-like structure, which is not applicable to sponges.
- **Muscular Pharynx**: This structure is related to more complex organisms and is not found in sponges.
- **Ostea**: These are the small pores on the body of the sponge through which water enters.

4. **Conclusion**:
- Based on the analysis, the correct answer is **D) Ostea**. Water enters the body of sponges through these small pores.

### Final Answer:
Water enters the body of sponges through **Ostea**.

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