Nitrogenous wastes in the Malpighian tubules flow into the

The correct answer is Intestine

Explanation:

• Malpighian tubules are excretory and osmoregulatory structures found in insects. They play a crucial role in eliminating nitrogenous wastes and maintaining water balance.
• Malpighian tubules are slender, thread-like structures located in the abdomen of cockroaches and many other insects. They are attached to the junction of the midgut and hindgut.
• Functionally, Malpighian tubules filter waste products from the hemolymph (the insect equivalent of blood) and then transport these wastes to the hindgut, where they are excreted from the body as solid uric acid crystals along with fecal matter.
• Cockroaches primarily excrete uric acid, which makes them uricotelic, not ureotelic.
• The excretion process in insects is closely tied to their digestive system, ensuring efficient removal of waste products.

Fig- Alimentary canal of Cockroach.

Other Options

• Coelom: Coelom is the body cavity found in many animals, but insects do not have a true coelom. Instead, they have a haemocoel, which is an open circulatory system. Malpighian tubules do not release wastes into a coelom because it does not exist in insects. 
• Haemocoel: The haemocoel is the primary body cavity in insects where haemolymph circulates. While Malpighian tubules extract wastes from the haemocoel, they do not release them back into it.
• Blood vessels: Insects have an open circulatory system, meaning they do not have closed blood vessels like vertebrates. Malpighian tubules interact with haemolymph, not blood vessels.