Osphradium is a structure in Pila/molluscs. It is a

Options

A. Sensory organ for smell and chemicals/chemoreceptor
B. Sensory organ for balancing
C. Swimming organ
D. Locomotory organ.

Answer

### Step-by-Step Solution:

1. **Understanding Osphradium**: Osphradium is a structure found in some molluscs, including Pila. It is important to identify its function and classification.

2. **Identifying the Function**: The primary function of the Osphradium is to serve as an olfactory organ. This means it is involved in the sense of smell.

3. **Association with Other Organs**: The Osphradium is also associated with the respiratory system of molluscs. This indicates that it plays a role in both sensing chemicals in the water and possibly in respiration.

4. **Sensory Role**: As an olfactory organ, the Osphradium helps molluscs to detect chemicals in the water, which can indicate the presence of food or other important environmental factors.

5. **Conclusion**: Based on the functions and characteristics of the Osphradium, the correct answer to the question is that it is a sensory organ for smell and taste.

### Final Answer:
Osphradium is a sensory organ for smell and taste.

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