Explanation of the correct answers:
B. Urecose gland - In cockroaches, the urecose gland is responsible for excretion. It is a type of excretory gland that helps in the elimination of waste products.
C. Nephrocytes - Nephrocytes are specialized cells in the cockroach's Malpighian tubules that play a crucial role in excretion. Malpighian tubules are the primary excretory organs in insects.
D. Fat body - While the fat body in insects has various functions, including energy storage, it is not directly involved in excretion.
The other options are incorrect:
A. Phallic gland - The phallic gland in male cockroaches is associated with the reproductive system and is not involved in excretion.
E. Collaterial glands - Collaterial glands in cockroaches are associated with the female reproductive system and play a role in the formation of the ootheca (egg case), but they are not excretory structures.
So, the correct option is (B): B, C and D only