The number of gills in Bivalvia are

Options

A. Two
B. Eight
C. Ten
D. Five

Answer

**Step-by-Step Solution:**

1. **Understanding Bivalvia**: Bivalvia is a class within the phylum Mollusca. Members of this class are commonly known as bivalves, which include clams, oysters, and mussels.

2. **Identifying the Number of Gills**: Bivalves typically possess two gills. These gills are essential for their respiratory and feeding processes.

3. **Location of Gills**: The gills in bivalves are located between the visceral hump and the mantle. The visceral hump contains the internal organs, while the mantle is a significant part of the bivalve's anatomy that covers the visceral mass.

4. **Function of Gills**: The primary functions of the gills include respiration (breathing) and filter feeding. They also play a role in excretion.

5. **Conclusion**: Therefore, the number of gills in Bivalvia is two.

**Final Answer**: The number of gills in Bivalvia is two.

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