On the basis of coelom, the hemichordates are

Options

A. Pseudocoelomates
B. coelomates
C. Acoelomates
D. both (1) and (2)

Explanation

**Step-by-Step Solution:**

1. **Understanding Coelom:**
- Coelom is defined as a body cavity that is located between the body wall and the intestinal canal. It serves as a space for the internal organs and can be filled with fluid.

2. **Identifying Hemichordates:**
- Hemichordates are a group of marine animals that exhibit certain characteristics, including the presence of a coelom.

3. **Classifying Hemichordates Based on Coelom:**
- Hemichordates possess a true coelom, which means they are classified as coelomates. This is because they have a body cavity that is completely lined by mesodermal tissue.

4. **Evaluating the Options:**
- **Option 1: Pseudocoelomates** - This is incorrect. Pseudocoelomates have a body cavity that is not entirely lined by mesoderm.
- **Option 2: Coelomates** - This is correct, as hemichordates have a true coelom.
- **Option 3: Acoelomates** - This is incorrect. Acoelomates lack a body cavity altogether.
- **Option 4: Both first and second** - This is incorrect since only the second option is correct.

5. **Conclusion:**
- The correct classification of hemichordates based on the presence of coelom is that they are **coelomates**.

**Final Answer:**
- Hemichordates are coelomates.

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