The body of cockroach is divided into three parts , Head, thorax and abdomen.
In it spiracles are present in pair, there are 10pair of spiracles. where two pair of spiracles present in thoracic and eight pair are found in abdominal.... so option D is correct

The correct answer is option 'D', which is 10 pairs of spiracles in a cockroach.

Cockroaches belong to the class Insecta and have a specialized respiratory system that allows them to breathe. This system consists of a network of tubes called tracheae, which deliver oxygen directly to the tissues. The tracheae are connected to the outside environment through small openings called spiracles.

Here is a detailed explanation of the number of pairs of spiracles in a cockroach:

1. Introduction to Spiracles:
Spiracles are small openings located on the sides of the body of an insect. They serve as the primary entrance and exit points for air in the respiratory system. In cockroaches, the spiracles are arranged in pairs along the sides of the body.

2. Location of Spiracles:
Cockroaches have spiracles running along the thorax and abdomen. The thoracic spiracles are located on the sides of each segment of the thorax, while the abdominal spiracles are found on the sides of each abdominal segment.

3. Number of Spiracles:
In a cockroach, there are 2 pairs of spiracles on the thorax and 8 pairs on the abdomen. This gives a total of 10 pairs of spiracles.

4. Thoracic Spiracles:
The thoracic spiracles are located on each of the three segments of the thorax. Each segment has a pair of spiracles, making a total of 2 pairs. These spiracles allow air to enter and exit the tracheal tubes, delivering oxygen to the flight muscles and other tissues in the thorax.

5. Abdominal Spiracles:
The abdominal spiracles are present on each of the eight segments of the abdomen. Each segment has a pair of spiracles, resulting in a total of 8 pairs. These spiracles provide oxygen to the abdominal organs and other tissues.

6. Importance of Spiracles:
Spiracles play a crucial role in the respiratory system of cockroaches. They allow air to enter the tracheal system, which then delivers oxygen directly to the tissues. The spiracles can be opened or closed by valves to regulate the flow of air and prevent water loss.

In conclusion, cockroaches have a total of 10 pairs of spiracles - 2 pairs on the thorax and 8 pairs on the abdomen. These spiracles are essential for the cockroach's respiratory system, allowing it to breathe and deliver oxygen to different parts of the body.