An example of scyphozoa is

Options

A. Catfish
B. jelly fish
C. Silver Fish
D. Cuttlefish

Answer

### Step-by-Step Solution:

1. **Understanding Scyphozoa**: Scyphozoa is a class within the phylum Cnidaria. It is commonly referred to as the class of true jellyfish.

2. **Characteristics of Scyphozoa**: Members of this class are marine invertebrates that are primarily gelatinous in structure. They do not possess a head or specialized organs for respiration and excretion.

3. **Body Forms**: Scyphozoans exist in two forms: the Medusa form, which is umbrella-shaped, and the Polyp form, which resembles a vase with tentacles.

4. **Movement**: Scyphozoans move in water by contracting and relaxing their muscles, allowing them to propel themselves.

5. **Identifying an Example**: The question asks for an example of Scyphozoa. Among the given options, jellyfish is the correct example as it falls under the Scyphozoa class.

6. **Elimination of Other Options**:
- **Option 1: Catfish** - This belongs to the phylum Chordata, not Scyphozoa.
- **Option 3: Silverfish** - This is an insect from the class Insecta within the phylum Arthropoda, not Scyphozoa.
- **Option 4: Cuttlefish** - This belongs to the class Cephalopoda within the phylum Mollusca, also not Scyphozoa.

7. **Conclusion**: The only valid example of Scyphozoa from the options provided is jellyfish.

### Final Answer:
An example of Scyphozoa is **jellyfish**.

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