The most natural concept of individuality of sponges, based on morphological and physiological aspect is

Options

A. ostia and canal system
B. osculum and canal system
C. ostia and diploblastic body
D. osculum and choancytes

Answer

To answer the question regarding the most natural concept of individuality of sponges based on morphological and physiological aspects, we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding the Structure of Sponges**:
- Sponges belong to the phylum Porifera and are characterized by their unique body structure, which includes numerous pores (ostia) and a complex canal system.

2. **Identifying Key Features**:
- The two primary features that highlight the individuality of sponges are the ostia and the canal system. Ostia are small pores that allow water to enter the sponge, while the canal system facilitates the movement of water throughout the sponge's body.

3. **Function of Ostia**:
- Ostia serve multiple functions: they allow the entry of water, help in the selection of food particles, and assist in the removal of waste products. This active pumping mechanism is crucial for the sponge's feeding and respiration.

4. **Understanding the Canal System**:
- The canal system in sponges is an exclusive feature of the phylum Porifera. It can be classified into three types: asconoid, syconoid, and leuconoid, with each type representing a different level of complexity in water flow and filtration.

5. **Comparing Other Options**:
- Other options such as the osculum, osteoendiploblastic body, and phagocytes do not encapsulate the individuality of sponges as effectively as the ostia and canal system. The osculum is merely an outlet for water, while the osteoendiploblastic body and phagocytes are features that can also be found in other organisms.

6. **Conclusion**:
- Based on the morphological and physiological aspects, the ostia and canal system collectively represent the most remarkable feature of sponges, emphasizing their individuality.

### Final Answer:
The most natural concept of individuality of sponges, based on morphological and physiological aspects, is the **ostia and canal system**.

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