Respiratory system is derived from

Options

A. Endoderm
B. Mesoderm
C. Ectoderm
D. None of these

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the embryonic origin of the respiratory system in animals.

2. **Identifying the Germ Layers**: During embryonic development, three primary germ layers are formed: ectoderm, mesoderm, and endoderm. Each layer gives rise to different organs and systems in the body.

3. **Function of the Respiratory System**: The respiratory system is responsible for the exchange of gases, specifically oxygen (O2) and carbon dioxide (CO2). It includes organs such as the lungs, bronchi, and alveoli.

4. **Determining the Origin of the Respiratory System**: The respiratory system, including its components like the bronchi and alveoli, develops from the endoderm layer during embryonic development.

5. **Conclusion**: Based on the information gathered, the correct answer to the question is that the respiratory system is derived from the **endoderm**.

### Final Answer:
The respiratory system is derived from the **endoderm**.

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