In cockroach `O_(2)` is carried to tissue by :

Options

A. Haemoglobin and haemocyanin
B. Blood plasma
C. Tracheal tubes
D. Diifusion through integument

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks how oxygen is transported to tissues in a cockroach. This involves understanding the respiratory system of cockroaches.

2. **Identifying Options**: The options provided are:
- Haemoglobin and haemocyanin
- Blood plasma
- Tracheal tubes
- Diffusion through integument

3. **Analyzing the Respiratory System of Cockroaches**:
- Cockroaches do not have a circulatory system that uses blood like mammals. Instead, they have a unique respiratory system that relies on tracheal tubes.
- These tracheal tubes are a network of air-filled tubes that directly deliver oxygen to the tissues.

4. **Role of Spiracles**:
- Cockroaches have small openings on the sides of their bodies called spiracles.
- These spiracles allow oxygen-rich air to enter the tracheal system.

5. **Gas Exchange Process**:
- Once the air enters through the spiracles, it travels through the tracheal tubes, where oxygen diffuses directly into the body tissues.
- Simultaneously, carbon dioxide produced by the cells diffuses into the tracheal tubes and is expelled back through the spiracles.

6. **Conclusion**:
- Given that cockroaches do not have hemoglobin and their blood is known as hemolymph, which does not carry oxygen in the same way as blood in vertebrates, the correct answer to the question is that oxygen is carried to tissues by **tracheal tubes**.

### Final Answer:
In cockroaches, oxygen is carried to tissues by **tracheal tubes**.

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