Ammonites are fossil shell remains of

Options

A. pelecypods
B. cephalopods
C. gastropods
D. scaphopods

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the classification of ammonites and what group of organisms they belong to.

2. **Identifying the Options**: The options provided are:
- Palycypores
- Cephalopods
- Gastropods
- Scaphopods

3. **Analyzing Each Option**:
- **Palycypores**: This group includes bivalves like oysters, which do not relate to ammonites.
- **Cephalopods**: This group includes organisms like octopuses and squids. Ammonites are indeed part of this group.
- **Gastropods**: This group includes snails and slugs, which are not related to ammonites.
- **Scaphopods**: This group includes tusk shells like Dentalium, which also do not relate to ammonites.

4. **Conclusion**: Based on the analysis, ammonites are fossil shell remains of cephalopods. They are extinct marine mollusks that share similarities with the living fossil Nautilus.

5. **Final Answer**: Therefore, the correct answer is **cephalopods**.

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