Oxygen is carried to the tissue of cockroach by which organ :

Options

A. Skin
B. Trachea
C. Plasma
D. Respiratory pigment

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which organ is responsible for carrying oxygen to the tissues of a cockroach.

2. **Analyzing the Options**:
- **Option A: Skin**: The skin is not involved in oxygen transport in cockroaches, so this option can be eliminated.
- **Option B: Trachea**: The trachea are specialized tubes in insects, including cockroaches, that facilitate gas exchange. This option seems promising.
- **Option C: Plasma**: Plasma is the liquid component of blood and does not carry oxygen in cockroaches, so this option can also be eliminated.
- **Option D: Respiratory Pigment**: Cockroaches do not have respiratory pigments like hemoglobin, which are found in other animals for oxygen transport. Therefore, this option is incorrect.

3. **Identifying the Correct Answer**: Based on the analysis, the trachea (Option B) is the correct organ that carries oxygen to the tissues of the cockroach.

4. **Conclusion**: The answer to the question is that oxygen is carried to the tissues of the cockroach by the trachea.

**Final Answer**: Option B: Trachea.

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