Comb jellies or sea walnuts are placed under

Options

A. Cnidaria
B. Ctenophora
C. Echinodermata
D. Annelida

Answer

**Step-by-Step Solution:**

1. **Identify the Organisms**: The question asks about comb jellies or sea walnuts. These are specific types of marine animals.

2. **Review the Options**: The options provided are:
- A) Sinadria
- B) Cetanophora
- C) Echinodermata
- D) Annelida

3. **Understand the Characteristics**: Comb jellies and sea walnuts are known for their unique features. They are part of a group of organisms that are characterized by their gelatinous bodies and the presence of cilia (tiny hair-like structures) that they use for movement.

4. **Determine the Correct Phylum**: Based on the characteristics of comb jellies and sea walnuts, they belong to the phylum Cetanophora. This phylum includes organisms commonly referred to as comb jellies or sea walnuts.

5. **Eliminate Incorrect Options**:
- Sinadria is not a recognized phylum related to comb jellies.
- Echinodermata includes starfish and sea urchins, which are not related to comb jellies.
- Annelida refers to segmented worms, which also do not include comb jellies.

6. **Conclude the Answer**: Since comb jellies and sea walnuts belong to the phylum Cetanophora, the correct answer is B) Cetanophora.

**Final Answer**: B) Cetanophora

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