Characteristic odour of Cockroach is produced by

Options

A. Dermal glands
B. Stink glands
C. Trichogen cells
D. Both A and B

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the source of the characteristic odor produced by cockroaches.

2. **Identifying the Options**: The options provided are:
- A) Thermal glands
- B) Stink glands
- C) Trichogen cells
- D) Both A and B

3. **Analyzing the Options**:
- **Thermal Glands**: These glands are located in the subcuticular region of cockroaches and do not produce any characteristic odor. Therefore, this option is incorrect.
- **Stink Glands**: These specialized glands are responsible for producing pheromones, which are chemical signals that create a characteristic odor. They are located in the fifth and sixth tergites of the cockroach's abdomen. This option is correct.
- **Trichogen Cells**: These cells are involved in the formation of hair-like structures on the cuticle and do not contribute to any specific odor. Thus, this option is also incorrect.
- **Both A and B**: Since option A is incorrect, this option cannot be correct.

4. **Conclusion**: The characteristic odor of cockroaches is produced by the **stink glands**.

### Final Answer:
The characteristic odor of cockroaches is produced by **stink glands**.

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