Balanoglossus has

Options

A. no - coelom
B. well developed coelom
C. reduced coelom
D. coelom only in embryonic stage

Answer

To solve the question regarding Balanoglossus, we need to analyze the characteristics of this organism and its classification within the phylum Hemichordata.

### Step-by-Step Solution:

1. **Identify the Organism**: Balanoglossus is a type of marine organism classified under the phylum Hemichordata. It is also known as an acorn worm.

2. **Understand Coelom**: The term "coelom" refers to the body cavity that is present between the body wall and the gut wall. It is important to understand the types of organisms based on their coelom structure:
- **Coelomates**: Organisms with a fully developed coelom surrounded by mesoderm.
- **Acoelomates**: Organisms that lack a coelom.
- **Pseudocoelomates**: Organisms with a body cavity that is not completely lined by mesoderm.

3. **Determine the Type of Coelom in Hemichordates**: Hemichordates, including Balanoglossus, possess a well-developed coelom. This means they have a true coelom that is fully formed and surrounded by mesoderm.

4. **Conclusion**: Since Balanoglossus has a well-developed coelom, the correct answer to the question is that Balanoglossus has a well-developed coelom.

### Final Answer:
Balanoglossus has a well-developed coelom.

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