Teredo is a

Options

A. Bivalve
B. Gastropod
C. Scaphopod
D. Siphonopod

Answer

**Step-by-Step Solution:**

1. **Identify the Organism:** The question asks about "Teredo." It is important to recognize that Teredo is a genus of marine bivalve mollusks.

2. **Understand the Classification:** Teredo belongs to the class Bivalvia, which is characterized by having two hinged shells (valves). This classification is crucial to answering the question correctly.

3. **Common Name:** Teredo is commonly known as "shipworm." This name arises from their habitat and behavior, as they bore into wood, particularly in marine environments.

4. **Habitat and Behavior:** Teredo species live in tunnels they create in wood, which is a unique adaptation among mollusks. This behavior distinguishes them from other bivalves that may not have such a lifestyle.

5. **Shell Composition:** The shells of bivalves, including Teredo, are primarily composed of calcium carbonate, which is a common characteristic of this class.

6. **Conclusion:** Based on the classification and characteristics outlined, Teredo is correctly identified as a bivalve mollusk.

**Final Answer:** Teredo is a bivalve.

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