Respiration by tracheal system occurs in

Options

A. frog
B. rat
C. earthworm
D. cockroach

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the organisms that utilize a tracheal system for respiration.

2. **Identifying the Options**: The options provided are:
- Frog
- Rat
- Earthworm
- Cockroach

3. **Analyzing Each Option**:
- **Frog**: Frogs primarily breathe through their skin (cutaneous respiration) and lungs, not a tracheal system.
- **Rat**: Rats breathe using lungs, which is a different respiratory system.
- **Earthworm**: Earthworms also respire through their skin, absorbing oxygen directly from the environment.
- **Cockroach**: Cockroaches, being insects, utilize a tracheal system for respiration. They have a network of air-filled tubes (tracheae) that transport oxygen directly to their tissues.

4. **Conclusion**: Based on the analysis, the organism that uses a tracheal system for respiration is the **cockroach**.

5. **Final Answer**: Respiration by tracheal system occurs in **cockroach**.

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