Coelom is formed by splitting of

Options

A. Mesoderm-skeleton
B. Ectoderm
C. Endoderm
D. All the above.

Answer

### Step-by-Step Solution:

1. **Understanding Coelom**: The coelom is defined as the true body cavity that is found in many animals. It is located between the outer body wall and the inner digestive tract.

2. **Formation of Coelom**: Coelom can be formed through two primary methods:
- **Schizocoely**: This is when the coelom forms by the splitting of the mesodermal tissue.
- **Enterocoely**: This occurs when the coelom develops from pouches of the archenteron (the primitive gut).

3. **Identifying the Correct Germ Layer**: The question asks about the germ layer responsible for the formation of the coelom.
- The options provided are:
- A) Mesoderm
- B) Ectoderm
- C) Endoderm
- D) All of the above

4. **Analyzing the Options**:
- **Mesoderm**: This is the germ layer that splits to form the coelom in the process of schizocoely.
- **Ectoderm and Endoderm**: These layers do not contribute to the formation of the coelom.

5. **Conclusion**: Since the coelom is formed by the splitting of the mesoderm, the correct answer is option A, mesoderm.

### Final Answer:
The coelom is formed by splitting of the **mesoderm** (Option A).

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