The class of Coelenterata which shows polymorphism is :

Options

A. hydrozoa
B. Scyphozoa
C. Anthozoa
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks which class of Coelenterata (now known as Cnidaria) exhibits polymorphism. Polymorphism refers to the existence of two or more distinct forms or stages in the life cycle of an organism.

2. **Defining Polymorphism in Cnidaria:** In the context of Cnidaria, polymorphism is commonly observed in certain classes where organisms can exist in different forms, such as polyps and medusae.

3. **Analyzing the Options:**
- **Option 1: Hydrozoa** - This class is known for exhibiting polymorphism. It includes both polyp and medusa forms. Polyps are typically the asexual stage, while medusae are the sexual stage.
- **Option 2: Scyphozoa** - This class primarily includes true jellyfish, which do not exhibit polymorphism as they mainly exist in the medusa form.
- **Option 3: Anthozoa** - This class includes corals and sea anemones, which do not show polymorphism as they exist only in the polyp form.
- **Option 4: All of these** - This option is incorrect since not all classes mentioned exhibit polymorphism.

4. **Conclusion:** Based on the analysis, the class of Coelenterata that shows polymorphism is **Hydrozoa**.

**Final Answer:** Hydrozoa

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