The correct option is B (a)−(iii),(b)−(i),(c)−(iv),(d)−(ii)
Gizzard or proventriculus is present in the foregut of the cockroach. It has thick circular muscles in its outer layer and six chitinous plates inside, called teeth. Gizzard is also called a grinding mill as it helps in grinding the food particles.
At the junction of foregut and midgut, there are 6-8 blind tubules called hepatic or gastric caeca which secrete digestive juices.
The respiratory system in cockroaches is called tracheal system, which consists of a network of tubes called trachea. Trachea opens on the lateral side of the body through 10 pairs of spiracles.
In the 10th segment of both sexes, a pair of jointed filamentous structures called anal cerci are present.
Hence, option a is correct.